Early data transmission in wireless communication system

ABSTRACT

Provided herein is design of early data transmission in wireless communication system. An apparatus for a user equipment (UE) includes a processor configured to: encode a physical random access channel (PRACH) sequence from a plurality of PRACH sequence for transmission via a PRACH to perform a random access procedure, wherein indication of support of early data transmission (EDT) that is transmitted during the random access procedure is based on at least one of the plurality of PRACH sequences, higher layer signaling, PRACH resources, PRACH formats, and a payload from the UE; and send the PRACH sequence to a radio frequency (RF) interface; and the RF interface to receive the PRACH sequence from the processor. Design of random access response (RAR) is also disclosed herein.

CROSS REFERENCES TO RELATED APPLICATIONS

This application claims priority to U.S. provisional patent applicationNo. 62/564,919 filed on Sep. 28, 2017, U.S. provisional patentapplication No. 62/586,718 filed on Nov. 15, 2017, U.S. provisionalpatent application No. 62/653,723 filed on Apr. 6, 2018 and U.S.provisional patent application No. 62/669,777 filed on May 10, 2018, allof which are incorporated herein by reference in their entirety for allpurposes.

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to wirelesscommunication, and in particular to design of early data transmission.

BACKGROUND ART

In a legacy wireless communication system, there is no data transmissionuntil radio resource control (RRC) connection setup is completed. Toreduce latency, early data transmission (EDT) is proposed recently,which is transmitted during a random access procedure. In other word,EDT is performed after physical random access channel (PRACH)transmission and before the RRC connection setup is completed. Design ofEDT will be described in the present disclosure.

SUMMARY

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a processor configured to:encode a physical random access channel (PRACH) sequence from aplurality of PRACH sequence for transmission via a PRACH to perform arandom access procedure, wherein indication of support of early datatransmission (EDT) that is transmitted during the random accessprocedure is based on at least one of the plurality of PRACH sequences,higher layer signaling, PRACH resources, PRACH formats, and a payloadfrom the UE; and send the PRACH sequence to a radio frequency (RF)interface; and the RF interface to receive the PRACH sequence from theprocessor.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a radio frequency (RF)interface to receive a random access response (RAR) from an access node;and a processor configured to: receive the RAR from the RF interface;decode the RAR to obtain an uplink (UL) grant; and determine whether theUL grant is used for scheduling of early data transmission (EDT) that istransmitted during a random access procedure.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a processor configured to:determine whether to monitor an explicit acknowledge (ACK) in responseto Msg3; and monitor the explicit ACK when it is determined to monitorthe explicit ACK; and a radio frequency (RF) interface to: receive theexplicit ACK.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a processor configured to:determine, based on an indicator, whether to allow the UE to go to anidle mode upon expiration of a timer after transmission of anacknowledge (ACK) in response to Msg4; and a radio frequency (RF)interface to: send the ACK to an access node that transmits the Msg4.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a processor configured to:determine a first candidate transport block size (TBS) value as thelargest candidate TBS value of a plurality of candidate TBS values; anddetermine, based on the first candidate TBS value, a target TBS valuefor transmission of Msg3 with early data transmission (EDT) that istransmitted during a random access procedure; and a memory interface tostore the first candidate TBS value.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a radio frequency (RF)interface to: receive a modulation and coding scheme (MCS)/transportblock size (TBS) indication field of an uplink (UL) grant or a resourceassignment field from an access node; and a processor configured to:receive the MCS/TBS indication field or the resource assignment fieldfrom the RF interface; and determine, based on the MCS/TBS indicationfield or the resource assignment field, a number of resource allocationunits for Msg3 with early data transmission (EDT) that is transmittedduring a random access procedure.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a processor configured to:decode a repetition number field of an uplink (UL) grant for Msg3 withearly data transmission (EDT) that is transmitted during a random accessprocedure to obtain a number of repetitions indicated by the repetitionnumber field; and determine a number of repetitions for a firstcandidate transport block size (TBS) value of a plurality of candidateTBS values based on the number of repetitions indicated by therepetition number field; and a memory interface to store the number ofrepetitions for the first candidate TBS value.

An embodiment of the disclosure provides an apparatus for a userequipment (UE), the apparatus comprising: a processor configured to:encode an indicator in a Msg3 with early data transmission (EDT) that istransmitted during a random access procedure, wherein the indicator isconfigured to indicate a target transport block size (TBS) valueselected by the UE; and a radio frequency (RF) interface to receive theindicator from the processor.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure will be illustrated, by way of example andnot limitation, in the figures of the accompanying drawings in whichlike reference numerals refer to similar elements.

FIG. 1 shows an example of a communication system in accordance withsome embodiments of the disclosure.

FIG. 2 is a flow chat illustrating a random access procedure inaccordance with some embodiments.

FIG. 3 illustrates example components of a device in accordance withsome embodiments of the disclosure.

FIG. 4 illustrates example interfaces of baseband circuitry inaccordance with some embodiments.

FIG. 5 is a block diagram illustrating components, according to someexample embodiments, able to read instructions from a machine-readableor computer-readable medium and perform any one or more of themethodologies discussed herein.

DETAILED DESCRIPTION OF EMBODIMENTS

Various aspects of the illustrative embodiments will be described usingterms commonly employed by those skilled in the art to convey thesubstance of their work to others skilled in the art. However, it willbe apparent to those skilled in the art that many alternate embodimentsmay be practiced using portions of the described aspects. For purposesof explanation, specific numbers, materials, and configurations are setforth in order to provide a thorough understanding of the illustrativeembodiments. However, it will be apparent to those skilled in the artthat alternate embodiments may be practiced without the specificdetails. In other instances, well known features may have been omittedor simplified in order to avoid obscuring the illustrative embodiments.

Further, various operations will be described as multiple discreteoperations, in turn, in a manner that is most helpful in understandingthe illustrative embodiments; however, the order of description shouldnot be construed as to imply that these operations are necessarily orderdependent. In particular, these operations need not be performed in theorder of presentation.

The phrase “in an embodiment” is used repeatedly herein. The phrasegenerally does not refer to the same embodiment; however, it may. Theterms “comprising,” “having,” and “including” are synonymous, unless thecontext dictates otherwise. The phrases “A or B” and “A/B” mean “(A),(B), or (A and B).”

FIG. 1 shows an example of a communication system 100 in accordance withsome embodiments of the disclosure. The communication system 100 isshown to include a user equipment (UE) 101. The UE 101 is illustrated asa smartphone (e.g., a handheld touchscreen mobile computing deviceconnectable to one or more cellular networks). However, it may alsoinclude any mobile or non-mobile computing device, such as a personaldata assistant (PDA), a tablet, a pager, a laptop computer, a desktopcomputer, a wireless handset, or any computing device including awireless communications interface.

In some embodiments, the UE 101 may include an Internet of Things (IoT)UE, which may include a network access layer designed for low-power IoTapplications utilizing short-lived UE connections. An IoT UE may utilizetechnologies such as machine-to-machine (M2M), machine-typecommunications (MTC), enhance MTC (eMTC), and narrow band IoT (NB-IoT)for exchanging data with an IoT server or device via a public landmobile network (PLMN), Proximity-Based Service (ProSe) ordevice-to-device (D2D) communication, sensor networks, or IoT networks.The M2M or MTC exchange of data may be a machine-initiated exchange ofdata. An IoT network describes interconnecting IoT UEs, which mayinclude uniquely identifiable embedded computing devices (within theInternet infrastructure), with short-lived connections. The IoT UEs mayexecute background applications (e.g., keep-alive messages, statusupdates, etc.) to facilitate the connections of the IoT network.

The UE 101 may be configured to connect, e.g., communicatively couple,with a radio access network (RAN) 110, which may be, for example, anEvolved Universal Mobile Telecommunications System (UMTS) TerrestrialRadio Access Network (E-UTRAN), a NextGen RAN (NG RAN), or some othertype of RAN. The UE 101 may operate in consistent with cellularcommunications protocols, such as a Global System for MobileCommunications (GSM) protocol, a Code-Division Multiple Access (CDMA)network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular(POC) protocol, a Universal Mobile Telecommunications System (UMTS)protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth generation(5G) protocol, a New Radio (NR) protocol, and the like.

The RAN 110 may include one or more access nodes (ANs). These ANs may bereferred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), nextGeneration NodeBs (gNBs), and so forth, and may include ground stations(e.g., terrestrial access points) or satellite stations providingcoverage within a geographic area (e.g., a cell). As shown in FIG. 1,for example, the RAN 110 includes AN 111 and AN 112. The UE 101 mayenable communicative coupling with the RAN 110 by utilizing connection103 with AN 111, as shown in FIG. 1. The AN 111 and AN 112 maycommunicate with one another via an X2 interface 113. The AN 111 and AN112 may be macro ANs which may provide lager coverage. Alternatively,they may be femtocell ANs or picocell ANs, which may provide smallercoverage areas, smaller user capacity, or higher bandwidth compared to amacro AN. For example, one or both of the AN 111 and AN 112 may be a lowpower (LP) AN. In an embodiment, the AN 111 and AN 112 may be the sametype of AN. In another embodiment, they are different types of ANs.

The AN 111 may terminate the air interface protocol and may be the firstpoint of contact for the UE 101. In some embodiments, the ANs 111 and112 may fulfill various logical functions for the RAN 110 including, butnot limited to, radio network controller (RNC) functions such as radiobearer management, uplink and downlink dynamic radio resource managementand data packet scheduling, and mobility management.

In accordance with some embodiments, the UE 101 may be configured tocommunicate using Orthogonal Frequency-Division Multiplexing (OFDM)communication signals with the AN 111 or with other UEs over amulticarrier communication channel in accordance various communicationtechniques, such as, but not limited to, an OrthogonalFrequency-Division Multiple Access (OFDMA) communication technique(e.g., for downlink communications) or a Single Carrier FrequencyDivision Multiple Access (SC-FDMA) communication technique (e.g., foruplink and Proximity-Based Service (ProSe) or sidelink communications),although the scope of the embodiments is not limited in this respect.The OFDM signals can include a plurality of orthogonal subcarriers.

In some embodiments, a downlink resource grid may be used for downlinktransmissions from the AN 111 to the UE 101, while uplink transmissionsmay utilize similar techniques. The grid may be a time-frequency grid,called a resource grid or time-frequency resource grid, which is thephysical resource in the downlink in each slot. Such a time-frequencyplane representation is a common practice for OFDM systems, which makesit intuitive for radio resource allocation. Each column and each row ofthe resource grid corresponds to one OFDM symbol and one OFDMsubcarrier, respectively. The duration of the resource grid in the timedomain corresponds to one slot in a radio frame. The smallesttime-frequency unit in a resource grid is denoted as a resource element.Each resource grid comprises a number of resource blocks, which describethe mapping of certain physical channels to resource elements. Eachresource block comprises a collection of resource elements; in thefrequency domain, this may represent the smallest quantity of resourcesthat currently can be allocated. There are several different physicaldownlink channels that are conveyed using such resource blocks.

The physical downlink shared channel (PDSCH) may carry user data andhigher-layer signaling to the UE 101. The physical downlink controlchannel (PDCCH) may carry information about the transport format andresource allocations related to the PDSCH channel, among other things.It may also inform the UE 101 about the transport format, resourceallocation, and Hybrid Automatic Repeat Request (HARD) informationrelated to the uplink shared channel. Typically, downlink scheduling(assigning control and shared channel resource blocks to the UE 101within a cell) may be performed at the AN 111 based on channel qualityinformation fed back from the UE 101. The downlink resource assignmentinformation may be sent on the PDCCH used for (e.g., assigned to) the UE101.

The PDCCH may use control channel elements (CCEs) to convey the controlinformation. Before being mapped to resource elements, the PDCCHcomplex-valued symbols may first be organized into quadruplets, whichmay then be permuted using a sub-block interleaver for rate matching.Each PDCCH may be transmitted using one or more of these CCEs, whereeach CCE may correspond to nine sets of four physical resource elementsknown as resource element groups (REGs). Four Quadrature Phase ShiftKeying (QPSK) symbols may be mapped to each REG. The PDCCH can betransmitted using one or more CCEs, depending on the size of thedownlink control information (DCI) and the channel condition. The PDCCHMAY be transmitted using one or more CCEs, depending on the size of thedownlink control information (DCI) and the channel condition. There maybe four or more different PDCCH formats defined in LTE with differentnumbers of CCEs (e.g., aggregation level, L=1, 2, 4, or 8)

Some embodiments may use concepts for resource allocation for controlchannel information that are an extension of the above-describedconcepts. For example, some embodiments may utilize an enhanced physicaldownlink control channel (EPDCCH) that uses PDSCH resources for controlinformation transmission. The EPDCCH may be transmitted using one ormore enhanced control channel elements (ECCEs). Similar to above, eachECCE may correspond to nine sets of four physical resource elementsknown as an enhanced resource element groups (EREGs). An ECCE may haveother numbers of EREGs in some situations.

The RAN 110 is shown to be communicatively coupled to a core network(CN) 120 via a S1 interface 114. In some embodiments, the CN 120 may bean evolved packet core (EPC) network, a NextGen Packet Core (NPC)network, or some other type of CN. In an embodiment, the S1 interface114 is split into two parts: the S1-mobility management entity (MME)interface 115, which is a signaling interface between the ANs 111 and112 and MMES 121; and the S1-U interface 116, which carries traffic databetween the ANs 111 and 112 and a serving gateway (S-GW) 122.

In an embodiment, the CN 120 may comprise the MMES 121, the S-GW 122, aPacket Data Network (PDN) Gateway (P-GW) 123, and a home subscriberserver (HSS) 124. The MMES 121 may be similar in function to the controlplane of legacy Serving General Packet Radio Service (GPRS) SupportNodes (SGSN). The MMES 121 may manage mobility aspects in access such asgateway selection and tracking area list management. The HSS 124 maycomprise a database for network users, including subscription-relatedinformation to support the network entities' handling of communicationsessions. The CN 120 may comprise one or several HSSs 124, depending onthe number of mobile subscribers, on the capacity of the equipment, onthe organization of the network, etc. For example, the HSS 124 canprovide support for routing/roaming, authentication, authorization,naming/addressing resolution, location dependencies, etc.

The S-GW 122 may terminate the S1 interface 113 towards the RAN 110, androutes data packets between the RAN 110 and the CN 120. In addition, theS-GW 122 may be a local mobility anchor point for inter-AN handovers andalso may provide an anchor for inter-3GPP mobility. Otherresponsibilities may include lawful intercept, charging, and some policyenforcement.

The P-GW 123 may terminate a SGi interface toward a PDN. The P-GW 123may route data packets between the CN 120 and external networks such asa network including an application server (AS) 130 (alternativelyreferred to as application function (AF)) via an Internet Protocol (IP)interface 125. Generally, the application server 130 may be an elementoffering applications that use IP bearer resources with the core network(e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). Inan embodiment, the P-GW 123 is communicatively coupled to an applicationserver 130 via an IP communications interface. The application server130 may also be configured to support one or more communication services(e.g., Voice-over-Internet Protocol (VoIP) sessions, PTT sessions, groupcommunication sessions, social networking services, etc.) for the UE 101via the CN 120.

The P-GW 123 may further be responsible for policy enforcement andcharging data collection. Policy and Charging Rules Function (PCRF) 126is a policy and charging control element of the CN 120. In a non-roamingscenario, there may be a single PCRF in the Home Public Land MobileNetwork (HPLMN) associated with a UE's Internet Protocol ConnectivityAccess Network (IP-CAN) session. In a roaming scenario with localbreakout of traffic, there may be two PCRFs associated with a UE'sIP-CAN session: a Home PCRF (H-PCRF) within a HPLMN and a Visited PCRF(V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF126 may be communicatively coupled to the application server 130 via theP-GW 123. The application server 130 may signal the PCRF 126 to indicatea new service flow and select the appropriate Quality of Service (QoS)and charging parameters. The PCRF 126 may provision this rule into aPolicy and Charging Enforcement Function (PCEF) (not shown) with anappropriate traffic flow template (TFT) and QoS class of identifier(QCI), which commences the QoS and charging as specified by theapplication server 130.

The quantity of devices and/or networks illustrated in FIG. 1 isprovided for explanatory purposes only. In practice, there may beadditional devices and/or networks, fewer devices and/or networks,different devices and/or networks, or differently arranged devicesand/or networks than illustrated in FIG. 1. Alternatively oradditionally, one or more of the devices of system 100 may perform oneor more functions described as being performed by another one or more ofthe devices of system 100. Furthermore, while “direct” connections areshown in FIG. 1, these connections should be interpreted as logicalcommunication pathways, and in practice, one or more intervening devices(e.g., routers, gateways, modems, switches, hubs, etc.) may be present.

In the present disclosure, design of EDT during a random accessprocedure will be described, in particular for eMTC (including enhancedfurther enhanced MTC (efeMTC) in Release 15) and NB-IoT (includingfurther enhanced NB-IoT (feNB-IoT) in Release 15) system. However, theembodiments of the present disclosure may also be applied to other LTEand 5G systems where early data transmission is supported, e.g. as apart of INACTIVE and light connection.

FIG. 2 is a flow chat illustrating a random access procedure inaccordance with some embodiments. In step 210, a UE (e.g., the UE 101 inFIG. 1) may transmit Message 1 (Msg1) to an AN (e.g., the AN 111) via aPRACH (or NPRACH for an NB-IoT system, collectively called PRACHherein). The Msg1 may include a PRACH sequence. After receiving theMsg1, in step 220, the AN may respond to the UE with Msg2 via e.g.,PDSCH. The Msg2 may include a random access response (RAR), which mayinclude uplink (UL) grant for the UE. In step 230, the UE may, inresponse to the Msg2, transmit Msg3 to the AN via, e.g., physical uplinkshare channel (PUSCH). The Msg3 may include a cell radio networktemporary identifier (C-RNTI) and a corresponding request, e.g.,rrcConnectionRequest, rrcConnectionReconfiigurationComplete,rrcConnectionReestablishmentRequest, and the like. In step 240, the ANmay, in response to the Msg3, transmit Msg4 to the UE via, e.g., PDSCH.The Msg4 may include contention resolution for the UE.

Design of UL grant in RAR and the design of Msg3 in a Release 13 eMTCsystem will be described first. Downlink control information (DCI)contents of the UL grant in the RAR are given by Table 1. A modulationscheme and/or coding rate and transport block size (TBS) may bedetermined from modulation and coding scheme (MCS) field. There are 8MCS indices, i.e., 0 through 7, for coverage enhancement (CE) mode A inaccordance with Table 8.6.1-1 in specification 36.213, and there are 4MCS indices, i.e., 0 through 3, for CE mode B in accordance with Table7.1.7.2.1-1 in specification 36.213. By reading these tables, the TBSvalues for Msg3 for CE mode A and CE mode B are summarized in Table 2and Table 3 respectively. As 4 bits are used for physical resource block(PRB) assignment in CE mode A, based on the calculation of resourceindication value (MV) which takes values from 0 to 15, the number ofallocated PRBs may not be 4 or 5. Thus, the TBS values for CE mode A mayonly be the values corresponding to number of PRBs 1, 2, 3 and 6 inTable 2.

TABLE 1 DCI contents of UL grant in RAR for an eMTC system Field sizefor Field size for DCI contents CE mode A CE mode B Description Msg3ceil(log2(number 2 NB index of Msg3 scheduling narrowband ofnarrowbands)) index PRB assignment 4 3 PRB location within theconfigured narrowband in narrowband index field. Repetition 2 3 Therepetition level of Msg 3 is number dynamically indicated based on a setof values configured by higher layers. MCS 3 2 MCS/TBS TPC 3 0 TPC issupported in CE mode A A-CSI 1 0 A-CSI is supported in CE mode A ULdelay 1 0 Msg3/4 2 2 NB index of MPDCCH carrying MPDCCH Msg3 ReTx andMsg4 narrow band index Total 20 12

TABLE 2 TBS values for Msg3 for CE mode A in an eMTC system TBS valuetable for CE mode A for Msg3 N_(PRB) I_(TBS) 1 2 3 4 5 6 0 16 32 56 88120 152 1 24 56 88 144 176 208 2 32 72 144 176 208 256 3 40 104 176 208256 328 4 56 120 208 256 328 408 5 72 144 224 328 424 504 6 328 176 256392 504 600 7 104 224 328 472 584 712

TABLE 3 TBS values for Msg3 for CE mode B in an eMTC system TBS valuetable for CE mode B for Msg3 N_(PRB) I_(TBS) 1 6 0 56 152 1 88 208 2 144256 3 176 328

For a Release 13 NB-IoT system, the DCI contents for UL grant in RAR isgiven by Table 4. The TBS value for Msg3 may only be 88 bits.

TABLE 4 DCI contents of UL grant in RAR for an NB-IoT system ContentsSize UL subcarrier spacing (3.75 kHz 1 bit or 15 kHz) Msg3 subcarrierallocation 6 bits (same as in UL grant) Resource assignment 3 bitsScheduling delay 2 bits (same as NPUSCH) MCS/TBS indication 3 bits (3states used to indicate the 3 (000 is pi/2 BPSK for ST and options forTBS = 88 bits from QPSK for MT, N_RU = 4 agreed NPUSCH MCS/TBS tables.001 is pi/4 QPSK for ST and Reserve the other states for future) QPSKfor MT, N_RU = 3 010 is pi/4 QPSK for ST and QPSK for MT, N_RU = 1Others are reserved) Repetition number 3 bits Other padding bits Asspecified by RAN2Indication of Support of Early Data Transmission and Applicability ofEarly Data Transmission

In some embodiments, the UE may encode a PRACH sequence for transmissionvia a PRACH to perform a random access procedure. The PRACH sequenceused by the UE may be selected from a plurality of PRACH sequences. Insome embodiments, support of EDT that is transmitted during the randomaccess procedure may be indicated by one or both of the UE and the AN.In an embodiment, the EDT may include UL transmission, for example, thetransmission via Msg3. In another embodiment, the EDT may includedownlink (DL) transmission, for example, the transmission via Msg2 orMsg4.

In some embodiments, the indication of support of EDT may be based on atleast one of higher layer signaling, PRACH resources, PRACH sequences,PRACH formats, and a payload from the UE.

In an embodiment, the higher layer signaling may be used to indicatewhether the AN supports EDT. In an embodiment, the higher layersignaling may include a system information (SI) message, such as masterinformation block (MIB), system information block 1 (SIB1), or systeminformation block 2 (SIB2). Explicit indication may be carried in the SImessage. For example, one bit in the SI message may be used to indicatewhether the AN supports the EDT. In an embodiment, the higher layersignaling may include dedicated higher layer signaling, such as RRCConnection Reconfiguration, or RRC Connection Release, and the like, toindicate whether the AN supports the EDT. In an embodiment, thededicated higher layer signaling may also be used by the AN (e.g., theAN 111) to enable/disable the usage of EDT in a given UE (e.g., the UE101). This information may also be forwarded or exchanged with the MME(e.g., the MME 121). Moreover, the MME may also inform the AN whetherthe UE is allowed or not to use EDT feature.

In some embodiments, PRACH resources, PRACH sequences, PRACH formats, ora payload from the UE may be used to indicate whether the UE supportsthe EDT.

In an embodiment, the PRACH resources/PRACH sequences are divided intodifferent partitions, and one or more partitions of the PRACHresources/PRACH sequences are configured to support the EDT. Forexample, besides the PRACH resources/sequences configured for a legacyrandom access procedure which does not support the EDT, e.g., in Release13, other sets of PRACH resources/sequences may be configured toindicate the support of EDT in Msg2/Msg3/Msg4.

In an embodiment, from the AN's aspect, different PRACHresources/sequences configured for UEs supporting EDT may indicate thesupport of EDT by corresponding AN implicitly.

In an embodiment, the PRACH resources may include one or both of timeresources and frequency resources. For example, a dedicated set of PRACHtime resources and/or PRACH frequency resources may be configured toindicate that the UE supports EDT in Msg3. In an embodiment wherefrequency domain resource partition is used for the indication,different frequency hopping patterns may be configured for differentpartitions.

As mentioned above, the partitioning in resources may be either in timedomain only, or frequency domain only, or in both time and frequencydomain. For example, if resource partitioning is used only in timedomain, the PRACH resources for UEs supporting EDT may be not overlappedwith the PRACH resources for UEs not supporting EDT. For example, thesubframes for UEs supporting EDT may be not overlapped with those forUEs not supporting EDT. As another example, if resource partitioning isused only in frequency domain, the PRACH frequency resources for UEssupporting EDT may be not overlapped with other PRACH frequencyresources for UEs not supporting EDT. For the NB-IoT system, thedifferent frequency resources may include a dedicated NB-IoT carrier, orN subcarriers (e.g. N=1 or 12). Alternatively, if both time andfrequency domain partitions are supported, it is up to the AN toconfigure a dedicated set of resources for UE supporting EDT. In thiscase, the PRACH resources for UE supporting EDT may be overlapped withPRACH resources for UEs not supporting EDT in time domain, or infrequency domain (but not in both).

In an embodiment, the partitions of the PRACH sequences are dividedbased on one or both of root indexes and cyclic shifts of the PRACHsequences. For example, different sets of root indexes and/or cyclicshifts of the PRACH sequences may be configured to indicate whether theUE supports EDT in Msg3. In an embodiment for the NB-IoT system, as anidentical NPRACH sequence is used, the partition may be in terms of timeand/or frequency domain resources.

In an embodiment, the partitions of the PRACH resources or PRACHsequences are further divided for different CE levels. Among theseresources/sequences allocated for EDT, the time/frequency resourcesand/or sequences can be further separated for different CE levels. Forexample, different time and/or frequency resources may be allocated todifferent CE levels supporting EDT. As another example, different setsof PRACH sequences may be configured for different CE levels supportingEDT. In this example, the time and/or frequency resources may be thesame or different for different CE levels. Herein, the term “CE level”may refers to both of CE mode A/CE mode B in the eMTC system andcoverage level in the NB-IoT system.

In some embodiments, the number of the partitions of the PRACH resourcesor PRACH sequences is configured to indicate support and/or requirementof multiple transport block size (TBS) values for EDT, e.g., the EDT viaMsg3.

In some embodiments, the partitions of the PRACH resources or PRACHsequences are further divided for UL transmission and DL transmission ofthe EDT separately or for both of the UL transmission and the DLtransmission of the EDT. For example, the PRACH resources/sequences arefurther partitioned to indicate whether the UE supports EDT in Msg3,supports EDT in Msg4, or support EDT in both Msg3 and Msg4.

In some embodiments, different PRACH formats may be defined for theindication of support of EDT. For example, the PRACH formats comprisessingle-tone PRACH and multi-tone PRACH, and the multi-tone PRACH mayindicate the UE supports EDT.

In some embodiments, the payload from the UE is used to indicate whetherthe UE supports the EDT. In some embodiment, the payload may be used toindicate a desired TBS value for EDT in Msg3.

In an embodiment, the payload may be transmitted following the PRACHsequence via PUSCH transmission. The modulation scheme and/or codingrate and time domain resources for the PUSCH transmission following thePRACH transmission may be predefined, which may depend on CE levels. ThePRACH may be used as the reference signal for demodulation of thepayload and thus, in an embodiment, there is no demodulation referencesignal (DMRS) symbols in the middle of PUSCH transmission. In anotherembodiment, the PUSCH format 1 or format 2 in LTE or NB-IoT may be usedto carry the encoded bits of the payload. Frequency domain resources ofthe PUSCH for the indication may be the same as that for the PRACHtransmission. Alternatively, frequency domain resources of the PUSCH forthe indication may be defined as a pre-defined function of the resourcesfor the PRACH transmission.

The embodiments of indication of support of EDT above may be applied toboth of UL transmission and DL transmission of EDT. For example, commonindication methods may be applied to both Msg3 and Msg4.

In some embodiments, EDT is enabled based on CE levels. In anembodiment, EDT in the eMTC system is enabled only in CE mode A, or onlyin CE mode B. Alternatively, EDT may be enabled for both CE mode A andCE mode B. In an embodiment, EDT in the NB-IoT system is enabled onlyfor UEs in a certain coverage level, e.g. a coverage level no higherthan X or no lower than X. For example, X may be an index to indicatecoverage levels, e.g. X=1. X may be defined in a standard or broadcastedin MIB or other SIBS. Alternatively, EDT may be enabled in all coveragelevels.

Design of RAR

In some embodiments, as mentioned above, the AN may, in response to thePRACH sequence from the UE, transmit a RAR to the UE. The UE may decodethe RAR to obtain a UL grant, and determine whether the UL grant is usedfor scheduling of EDT.

In some embodiments, whether the UL grant is used for scheduling of EDTmay be determined based on an indicator. The indicator may be carriedvia at least one of an additional bit in the UL grant, a reserved bit inthe RAR, an additional bit in the RAR other than the UL grant, a newfield in a medium access control (MAC) header of a MAC protocol dataunit (PDU) for the RAR, and a reserved state indicated by a field of theUL grant. The MAC PDU may include the MAC header, one or more RAR eachof which corresponds to a respective UE. Each RAR may include a UL grantfor corresponding UE and other information field.

In some embodiments, the additional bit in the UL grant, the reservedbit (e.g., the reserved bit “R”) in the RAR or the additional bit in theRAR other than the UL grant may indicate whether the UL grant is usedfor scheduling of EDT.

In some embodiments, the reserved bit in the RAR, e.g., the bit “R”, maybe used to indicate whether the UL grant is used for scheduling of EDTor the UE have to fall back to the legacy random access procedurewithout EDT. For example, R=0 may indicate the fall back operation andR=1 may indicate the scheduling of EDT, or vice versa.

In an embodiment where the additional bit in the RAR other than the ULgrant is used to indicate whether the UL grant is used for scheduling ofEDT, the resources used for PRACH may be shared among UEs supporting EDTand UEs not supporting EDT. This may cause confusion for pre-releaseUEs, which may also follow the additional bit to interpret the UL grantin the RAR to transmit Msg3. This may cause additional UE powerconsumption.

In some embodiments, the new field in the MAC header for the RAR mayindicate a starting RAR from which Msg3 with EDT will be supported forthis RAR and its subsequent RARs.

In some embodiments where the indicator is carried via one of theadditional bit in the UL grant, the reserved bit in the RAR, theadditional bit in the RAR other than the UL grant and the new field inthe MAC header for the RAR, for example, for an eMTC system, differentnumber of bits may be used in the PRB assignment field and/or MCS/TBSindication field for CE mode A and/or CE mode B to schedule EDT, e.g.,Msg3 with EDT.

In an embodiment, the UL grant may include a MCS/TBS indication fieldthat includes less bits than that for a random access procedure withoutEDT, e.g., the random access procedure in Release 13 where EDT is notsupported. For example, one bit may be used for MCS/TBS indication fieldto indicate the modulation order (e.g. QPSK or 16QAM), while the TBSvalue may be predefined, which, in an embodiment, may depend on CElevels.

In an embodiment, the UL grant may include a MCS/TBS indication fieldthat includes more bits than that for a random access procedure withoutEDT. More bits in the MCS/TBS indication field may be configured toindicate a larger range of TBS values. For example, 1 or 2 bits may beadded to a legacy MCS/TBS indication field, to indicate a wider range ofTBS values. For CE mode A, with additional N bits, the Imcs or Imsvalues may be 0 to 2^(N+3)−1 (e.g., 0 to 15 with N=1); and for CE modeB, with additional N bits, the Imcs or Ims values may be 0 to 2′4 (e.g.,0 to 7 with N=1). Alternatively, the Imcs or Ims values may be anysubset of {0, 1, 2, 3, . . . , 10}, e.g., {0, 1, 2, 3, 5, 7, 9, 10}. Inan example, only when the indicated Imcs or Ims value is larger thanwhat has been supported in Release 13, the UE may interpret that the EDTin Msg3 is scheduled, otherwise, UE may fall back to legacy Msg3transmission without EDT.

Compared with the random access procedure without ECT where the MCS/TBSindication field is only configured to indicate TBS values in CE mode B,the MCS/TBS indication field in an embodiment in accordance with thepresent disclosure is configured to indicate a combination of amodulation scheme (e.g., a modulation order) and/or coding scheme (e.g.,a coding rate) with a TBS value. For example, a plurality of bits may beused for the MCS/TBS indication field to indicate the modulation orderand/or coding scheme and TBS value, e.g., N=2 bits are used to indicate4 possible combinations of modulation schemes and/or coding schemes withTBS values.

In an embodiment, the UL grant may include a PRB assignment field thatincludes less bits than that for a random access procedure without EDT.The PRB assignment may be reduced, e.g. to 0 bit based on apredefinition. For example, 6 PRBs are allocated for EDT for CE mode Aand 2 PRBs are allocated for EDT for CE mode B. As another example, 2PRBs (e.g., the first or last 2 PRBs) are allocated for EDT for CE modeA and 1 PRB (e.g., the first or last one PRB) is allocated for EDT forCE mode B. Alternatively, the PRB assignment field may include one ormore bits. For example, one bit may be used to indicate two sets of PRBallocation, e.g. 3 (first or last 3 which may be predefined) or 6 PRBsfor CE mode A, and/or 1 (first or last one which may be predefined) or 2PRBs for CE mode B.

As mentioned above, in some embodiments, the additional bit in the ULgrant, the reserved bit in the RAR, or the additional bit in the RARother than the UL grant may indicate whether the UL grant is used forscheduling of EDT in an explicit way. In some embodiments, one of theadditional bit in the UL grant, the reserved bit in the RAR, and theadditional bit in the RAR other than the UL grant is configured toindicate whether a field in the UL grant is required to be interpretedin a different way from that for a random access procedure without EDT.In this way, the additional bit in the UL grant, the reserved bit in theRAR, or the additional bit in the RAR other than the UL grant may beconfigured to indicate whether the UL grant is used for scheduling ofEDT in an implicit way. Alternatively, another additional bit in the ULgrant, another reserved bit in the RAR, or another additional bit in theRAR other than the UL grant is configured to indicate whether a field inthe UL grant is required to be interpreted in a different way from thatfor a random access procedure without EDT.

If it is indicated to interpret in a different way from that for therandom access procedure without EDT, the MCS/TBS indication field may bere-interpreted. In some embodiments, compared with the TBS values in therandom access procedure without EDT, the MCS/TBS indication field may bere-interpreted to indicate one or more larger TBS values with an offsetto the TBS value in the random access procedure without EDT. In anembodiment, a set of offsets may be predefined or configured by higherlayer signaling. In an embodiment, the indication of offset to the TBSvalue is enabled based on different CE levels. In an embodiment,different offsets may be configured for different CE levels. In anembodiment, if the scheduled TBS value is smaller than a threshold (e.g.for the eMTC system), the UE will fall back to the legacy random accessprocedure without EDT. The threshold can be predefined orsemi-statically configured. In some embodiments, a new TBS table may bedefined, and the MCS/TBS indication field with the same size as that oflegacy random access procedure may be used to indicate different TBSvalues from that in the legacy random access procedure. In anembodiment, the new TBS table may be a truncated version of the existingTBS table, or a version with some elements replaced by larger TBSvalues. For example, a set of Ims values may be predefined orsemi-statically configured for random access procedure with EDT, and theMCS/TBS indication field may be used to indicate one of the ITBs values.

Instead of the offset(s) being predefined or configured by higher layersignaling, in some embodiments, the UL grant may include an additionalbit to indicate an offset to a TBS value. The additional bit to indicatean offset may be used in combination with the MCS/TBS indication fieldfor the eMTC system and/or for the NB-IoT system, to indicate additionaloffset to the TBS value indicated by the MCS/TBS indication field of theUL grant. In an embodiment, a set of offsets may be predefined orconfigured by higher layer signaling. In an embodiment, the indicationof offset to the TBS value is enabled based on different CE levels. Inan embodiment, different offsets may be configured for different CElevels.

In some embodiments, the UE may determine that the UL grant is used forscheduling of EDT, when the UE transmits a PRACH sequence via a PRACHresource that is dedicated for the EDT or the UE transmits a PRACHsequence dedicated for the EDT. As long as the UE transmits the PRACHsequence corresponding to the resources/sequences supporting EDT, the ULgrant will be re-interpreted in a way supporting EDT. In this example,the AN may not be able to schedule the same TBS as for legacy Msg3.

In some embodiments, the indicator to indicate whether the UL grant isused for scheduling of EDT is carried via a reserved state indicated bya field of the UL grant, for example, for an NB-IoT system. As 3 bitsare used for MCS/TBS indication field to indicate only 3 states, thereserve states may be used for the scheduling of EDT. This may beapplied regardless of how the PRACH resources are configured for UEssupporting and not support early data transmission. Once the UE detectsthat the MCS/TBS indication field has states other than 000, 001 or 010,the UE that does not supporting EDT would consider corresponding RAR asa failed detection. In an embodiments, less bits may be used in at leastone of a UL subcarrier spacing field, a Msg3 subcarrier allocationfield, a resource assignment field and a MCS/TBS indication field withinthe UL grant.

In an embodiment, for example, the supported sub-PRB allocations may belimited for EDT in Msg3. In an embodiment, only multi-tone PUSCH issupported for EDT. In this embodiment, the UL subcarrier spacing fieldis not necessary, thus, for example, the UL subcarrier spacing field maybe cancelled, and the size of the Msg3 subcarrier allocation filed maybe reduced. In an embodiment, only 15 kHz subcarrier spacing or only3.75 kHz subcarrier spacing is supported for EDT in Msg3. In thisembodiment, the UL subcarrier spacing field is not necessary, thus, forexample, the UL subcarrier spacing field may be cancelled. In anembodiment, the MCS/TBS indication field may have less bits, bypredefining a TBS value for EDT.

In some embodiments, format of the RAR in the random access procedurewith EDT may be the same as pre-release random access procedure withoutEDT. This may be applied to embodiments where dedicated PRACHresources/sequences are used for UEs supporting EDT, where the UE knowshow to interpret the UL grant scheduling EDT, or where a reserved stateis used for scheduling of EDT.

In some embodiments, the UE may perform the random access procedurewithout EDT when determining the UL grant is not used for scheduling ofEDT.

As mentioned above, in some embodiments, the bits included in a field ofthe UL grant or in the RAR may be reduced or additional bit(s) may beadded. The size of the UL grant in the random access procedure with EDTmay be the same as or different from that of the UL grant in the legacyrandom access procedure without EDT. Similarly, the size of the RAR inthe random access procedure with EDT may be the same as or differentfrom that of the RAR in the legacy random access procedure without EDT.

In an embodiment where the size of the UL grant in the random accessprocedure with EDT is different from that of the UL grant in the legacyrandom access procedure without EDT, the resources for PRACH are sharedamong UEs supporting EDT and UEs not supporting EDT. The UEs mayidentify whether this UL grant is for scheduling of EDT based on thesize of the UL grant. In one example of this embodiment, a new headercan be introduced to RAR to indicate the size of the UL grant, e.g. byindicating the starting and ending location of the UL grant in a newfield of the header. For example, in a MAC PDU, all the RARscorresponding to legacy random access procedure without EDT may be sentfirst, after which the RARs corresponding to Msg3 with EDT (whose sizemay be different from legacy RAR due to different size of UL grant) mayfollow.

Alternatively, in an embodiment where the size of the UL grant in therandom access procedure with EDT is different from that of the UL grantin the legacy random access procedure without EDT, the resources forPRACH are separated among UEs supporting EDT and UEs not supporting EDT.The PRACH resource configuration may ensure that all the RARs to becarried by Msg2 correspond to either UEs not supporting EDT or UEssupporting EDT. Then all the RARs carried in a MAC PDU may have the samesize. In this case, MAC header for RAR can be the same (no new field isneeded).

In an embodiment, the size of the UL grant in the random accessprocedure with EDT is the same as that of the UL grant in the legacyrandom access procedure without EDT, irrespective of early datatransmission support. A plurality of indication methods withoutreduction or addition of bit(s) in the UL grant described above may beapplied in this case.

ACK Indication of Msg3

During a random access procedure, the AN may transmit an acknowledge(ACK) in response to Msg3 received from the UE.

In some embodiments, Msg4 scheduling/transmission may serve as the ACKfor Msg3 with EDT, which is the same for Msg3 without EDT, e.g., inRelease 13. In these embodiments, there is no explicit ACK for Msg3 withEDT.

In some embodiments, an explicit ACK in response to Msg3 is introduced.These embodiments may be applied to both of Msg3 with EDT and Msg3without EDT, even though Msg3 with EDT are mainly described below.

In some embodiment, the UE may determine whether to monitor the explicitACK for Msg3 and the UE may monitor the explicit ACK once making adetermination to do so.

In some embodiments, whether to monitor the explicit ACK is determinedbased on at least one of Msg2, predefinition, and a SI message.

In an embodiment, the RAR for the UE in Msg2 may indicate whether tomonitor the explicit ACK by the UE. In an embodiment, the UE is alwaysassumed to monitor the explicit ACK. In an embodiment, the use of theexplicit ACK for Msg3 may be indicated by a SI message, such as MIB,SIB1, or SIB2, via some indication, for example, via a 1-bit informationin the SI message.

Whether to use the explicit ACK is described above. Then the indicationof the explicit ACK itself is described below.

In some embodiments, a new radio network temporary identity (RNTI) isdefined for PDCCH for scheduling Msg2, to indicate the explicit ACK.

In some embodiments, a temporary cell radio network temporary identity(Temp C-RNTI) is used for the PDCCH for scheduling Msg2, to indicate theexplicit ACK.

In some embodiments, a first unused value or a first reserved stateindicated by a field (e.g., the MCS/TBS indication field and/or the PRBassignment field) of the Msg2 is configured to indicate the explicitACK. For example, for CE mode A in the eMTC system, 5 bits are used forPRB assignment within each narrowband. There are 11 unused states thatare indicated by the 5 bits for indication of the explicit ACK in CEmode A. For example, for CE mode B in the eMTC system, the Ims is nolarger than 9, and thus there are 5 unused values that are indicated by4 bits in the MCS/TBS indication field. These unused values may be usedto indicate the explicit ACK for Msg3. For example, for the NB-IoTsystem, 4 bits in NPDCCH format N1 are used for MCS indication of Msg2.The number of Ims is up to 10 for in-band mode and 12 for guard-band andstandalone modes. There are at least 3 unused values that can be usedfor indication of the explicit ACK. For example, for the NB-IoT system,the explicit ACK may be indicated by one of the reserved statesindicated by the MCS/TBS indication field.

In an embodiment, a second unused value or a second reserved stateindicated by a field (e.g., the MCS/TBS indication field and/or the PRBassignment field) of the Msg2 is configured to indicate the UE to go toan idle mode (go back to sleep) after successful transmission of Msg3with EDT. In an embodiment, an unused value or a reserved stateindicated by a field (e.g., the MCS/TBS indication field and/or the PRBassignment field) of the Msg2 is configured to indicate the UE to go tothe idle mode after successful reception of Msg4 with EDT.

With configuration of the explicit ACK, in some embodiments, uponreception of such an explicit ACK, the UE may go to the idle mode, andno Msg4 scheduling is expected. For this case, the “ACK-only” earlyindication signal/channel may include the contention resolutioninformation or other information necessary to indicate contentionresolution that is carried in Msg4 in the legacy random accessprocedure.

In an embodiment, the UE may not simultaneously monitor the explicit ACKand PDCCH for scheduling Msg4 or Msg3 retransmission. A monitoringwindow for the explicit ACK may be predefined, or indicated by a SImessage, such as MIB, SIB1 or SIB2. Different monitoring windows may bepredefined or configured for different CE levels. Outside of themonitoring window, the PDCCH for scheduling of Msg3 retransmission orMsg4 may be monitored by the UE.

In an embodiment, the UE may monitor the explicit ACK and the PDCCHsimultaneously. Whichever comes earlier, the UE follows the indicationcorrespondingly.

With configuration of the explicit ACK, in some embodiments, it may beindicated by Msg2, e.g., the UL grant in the RAR, whether to go to theidle mode or continue to monitor for PDCCH for scheduling of Msg4 orMsg3 retransmission, upon reception of the explicit ACK.

In some embodiments, the UE may operate in the same way as that in thelegacy random access procedure without EDT once it is determined not tomonitor the explicit ACK, e.g., the UE may receive an ACK for the Msg3via Msg4 scheduling/transmission.

Scheduling of Msg4

In some embodiments, scheduling and/or transmission of Msg4 with EDTfollows the legacy random access procedure without EDT, for example, inRelease 13. Also, the UE's behavior after reception of Msg4 with EDTfollows the legacy random access procedure without EDT, for example, inRelease 13.

In some embodiments, an indication may be introduced to indicate whetherthe UE is allowed to go to the idle mode upon expiration of a timerafter transmission of an ACK in response to the Msg4 to the AN.

In an embodiment, the indication may be carried in a SI message, such asMIB, SIB1 or SIB2, and thus be a cell-specific configuration. In anembodiment, the indication may be carried in Msg2. In an embodiment, theindication may be carried in the PDCCH which schedules the(re)transmission of Msg4.

In an embodiment, the timer may be predefined or configured by a SImessage, such as MIB, SIB1 or SIB2. In an embodiment, different timersmay be predefined or configured based on different CE levels.

Whether to allow the UE to go to the idle mode is described above.Indication of UE release, e.g., going to the idle mode, may be describedbelow.

In an embodiment, a new RNTI may be defined for the PDCCH scheduling(re)transmission of Msg4, to indicate the UE to go to the idle mode.

In an embodiment, an unused value or a reserved state indicated by afield (e.g., the MCS/TBS indication field and/or the PRB assignmentfield) of Msg2 is configured to indicate the UE to go to the idle modeafter successful transmission of the ACK, as discussed for indication ofthe explicit ACK for Msg3 above. In an embodiment, the indication of UErelease by the unused value or a reserved state may be used when thePDCCH scheduling (re)transmission of Msg4 is used to carry the indicatorthat indicates whether to allow the UE to go to the idle mode uponexpiration of the timer after transmission of the ACK for Msg4.

How to Determine the Up to 4 Candidate TBS Values

RAN2 has discussed padding issues for EDT in Msg3. From RAN2 point ofview, it would be beneficial if the UE could choose a TBS value thatrequires minimum number of padding bits from a set of possible TBSvalues according to the UL grant in RAR.

The UL grant for Msg3 with EDT may allow the UE to choose an appropriateTBS value, MCS, repetitions, and resource allocation units (resourceunits (RUs) for the NB-IoT system) from a set of TBS values providedbased on the UL transmission. How to provide possible TBS values, MCS,repetitions, and RUs (for the NB-IoT system) has not been discussed.

Agreements have been made that the maximum TBS value broadcasted insystem information is selected from 8 values which are taken from theRel-13 PUSCH tables; up to 4 possible TBS values which are smaller thanor equal to the broadcasted maximum TBS value are available to the UE tochoose among. However, how the UE determines the up to 4 candidatevalues are for further studying.

In the present disclosure, it is to be discussed how to determine the upto 4 candidate TBS values by the UE below. Additional details will beprovided on the UL grant design to support the scheduling of up to 4candidate TBS values smaller than or equal to the maximum TBS valuebroadcasted by system information for the UE to choose among. However,the embodiments in the present disclosure are not limited in the numberof candidate TBS values available to the UE, and other numbers may beapplicable besides up to 4 candidate TBS values.

In some embodiments, the UE may determine a first candidate TBS value asthe largest candidate TBS value of a plurality of candidate TBS values.The UE then may determine, based on the first candidate TBS value, atarget TBS value for transmission of Msg3 with EDT.

In some embodiments, the first candidate TBS value is determined basedon a maximum TBS value indicated by a SI message, such as MIB, SIB1,SIB2, and the like. In an embodiment, the first candidate TBS value isdetermined to be equal to the maximum TBS value. In other words, thelargest candidate TBS value among the plurality of candidate TBS valuesmay be equal to the maximum TBS value broadcasted by the SI message. Inan embodiment, the first candidate TBS value is determined based on bothof the maximum TBS value and the number of resource allocation unitsallocated to the UE. For example, the first candidate TBS value isdetermined to be a TBS value of a plurality of TBS values correspondingthe allocated number of resource allocation units. The TBS value is thelargest one of the plurality of TBS values that is equal to or smallerthan the maximum TBS value.

In some embodiments, the first candidate TBS value is determined basedon the MCS/TBS indication field in the UL grant for the Msg3 with EDT.The TBS value indicated by the MCS/TBS indication field is used as thelargest candidate TBS value, and it is no more than the maximum TBSvalue broadcasted by the SI message.

For the other candidate TBS values, the following methods may beconsidered to determine their values. For ease of description, up to 4candidate TBSs values are illustrated in the embodiments below. Asmentioned above, the embodiments in the present disclosure are notlimited in the number of candidate TBS values available to the UE, andother numbers may be applicable besides up to 4 candidate TBS values.The plurality of candidate TBS values may be denoted by X_(i) (“i” is aninteger). In the embodiments where there are up to 4 candidate TBSvalues, the largest candidate TBS value may be denoted by X₀, and theother up to 3 candidate TBS values may be denoted by X₁, X₂ and X₃.

In some embodiments, the other up to 3 candidate TBS values X₁, X₂ andX₃ may be determined based on the largest candidate TBS value X₀. Insome embodiments, X₁, X₂ and X₃ may be determined based on a mappingbetween X₀ and X₁, X₂ and X₃. For example, a predefined mapping from X₀to the set {X₁, X₂, X₃} may be used. Note that for a certain value ofX₀, it is possible that it may only map to {X₁, X₂} or {X₁}, or evenonly X₀ is the possible TBS value to be selected by the UE. For example,when X₀ is around 320 bits which is close to the minimum possible TBSvalue supported for Msg3 with EDT, there is no need to further supportother possible smaller TBS values for UE to choose.

In an embodiment, the mapping between X₀ and {X₁, X₂, X₃} may include atable indicating X₀ and corresponding X₁, X₂ and X₃. The table may bepredefined. By referring to the table, the UE may know the values of theother up to three smaller candidate TBS values that can be used. Asmentioned above, based on the value of X₀, it is possible that some rowsof the table for certain values of X₀ may correspond to nothing or asubset of {X₁, X₂, X₃}. Table 5 below provides an example of the tableto map X₀ to values for {X₁, X₂, X₃}. Table 5 is an example, and theembodiments are not limited in this respect.

TABLE 5 Mapping table indicating X₀ and other candidates TBS values X₀Other candidate TBS values ~1000 328, 584, 776 ~936 328, 504, 712 ~808328, 504, 680 ~712 328, 456, 586 ~600 328, 424, 504 ~504 328, 424 ~424328 ~328 N/A

In Table 5, as can be seen, there is a sign “˜” before the value of X₀.It means the value of X₀ may include other candidate TBS values for X₀around the listed values above.

In some embodiments, the other candidate TBS values in the table providea reference, rather than actual ones. The actual candidate TBS valuesmay be based on the number of resource allocation units indicated by theUL grant. The resource allocation units herein may include PRBs (in theeMTC system or LTE system) or resource units (RUs) and/or subcarries (inthe NB-IoT system). The actual candidate TBS values to be selected by UEare determined by the TBS values in the column corresponding to thenumber of scheduled PRBs in Table 7.1.7.2.1-1 in 36.213 for the eMTCsystem or the number of indicated RUs in Table 16.5.1.2-2 in 36.213 forthe NB-IoT system, which are closest to the values given by the mappingtable above. For example, in the eMTC system, if X₀ is 1000 bits andnumber of scheduled PRBs is 6, the candidate TBS values would be 328,600, 808 and 936 which are the supported TBS values by reading columncorresponding to 6 PRBs in Table 7.1.7.2.1-1 in 36.213. Similarly, inthe NB-IoT system, if X₀ is 1000 bits and I_(RU) is 5, the candidate TBSvalues would be 328, 600, 808 and 1000 bits.

Alternatively, in some embodiments, the other candidate TBS values inthe table may provide exact candidate TBS values (i.e., the actual ones)to be selected by the UE. In an embodiment, the number of PRBs/RUsaccording to these candidate TBS values (the largest one and othersmaller ones) may be determined by the largest number that is smaller orequal to the number of PRBs/RUs indicated by the UL grant and has thecorresponding TBS values in its corresponding column in Table7.1.7.2.1-1 in 36.213 and Table 16.5.1.2-1 in 36.213, respectively. Forexample, in the eMTC system, if X₀ is 936 bits and number of PRBsindicated by the UL grant is 6, the number of PRBs, when UE selects TBSvalues of 328, 584, 776 and 936, would be 6, 5, 5 and 6 respectively.Similarly, for example, in the NB-IoT system, if X₀ is 1000 bits andI_(RU) indicated by the UL grant is 5, the I_(RU), when the UE selectsTBS values of 328, 584, 776 and 936, would be 5, 4, 4 and 5respectively. When the number of PRBs or RUs is less than that indicatedby the UL grant, a subset of resources would be used by the UE, e.g. theset of starting PRBs or the set of starting subframes among theallocated ones indicated by the UL grant may be used by the UE.

In some examples, a common mapping table may be used for different CElevels. Alternatively, different mapping tables may be defined fordifferent CE levels.

In an embodiment, the mapping between X₀ and X₁, X₂ and X₃ may include afunction between the X₀ and corresponding X₁, X₂ and X₃. For example,X₁=f(X₀/4), X₂=f(X₀/2), and X₃=f(X₀*¾), where f may be a function, suchas a ceil function, a floor function, a round function or otherfunctions.

In some examples, a common function may be used for different CE levels.Alternatively, different functions may be defined for different CElevels.

In an embodiment, the calculated X_(i) based on the function may beconsidered as a reference value. The actual candidate TBS value(s) to beselected by the UE may be obtained by choosing the value(s) closest tothe respective reference value X_(i).

In some embodiments where the first candidate TBS value is determinedbased on a maximum TBS value indicated by a SI message, the MCS/TBSindication field in the UL grant may be used to indicate one othersmaller candidate TBS values, e.g., {X₁, X₂, X₃}. For example, thesmallest candidate TBS value that can be selected by the UE may beindicated by the MCS/TBS indication field.

In an embodiment, the UE may determine only up to two candidate TBSvalues (i.e., the TBS value indicated by the MCS/TBS indication fieldand the maximum TBS value broadcasted by the SI message).

In an embodiment, the UE may still determine up to 4 candidate TBSvalues. The TBS value indicated by the MCS/TBS indication field and themaximum TBS value broadcasted by the SI message provide the range todetermine the other two candidate TBS values. For example, the candidateTBS value indicated by the MCS/TBS indication field serves as thesmallest candidate TBS value that can be selected by the UE, denoted byX₃, the maximum TBS value broadcasted by the SI message serves as thelargest candidate TBS value X₀, then the X₁ and X₂ may be any two valuesbetween X₀ and X₃, e.g. X₁=f((X₀−X₃)*⅔+X₃) and X₂=f((X₀−X₃)/3+X₃).Function f(x) may be ceil(x), floor(x), round(x), etc. In an optionalembodiment, the calculated X₁ may be considered as a reference valuewhere the actual candidate TBS value(s) to be selected by the UE may beobtained by choosing the value(s) closest to the respective referencevalue X₁.

In some embodiments, the UE is configured to use the same frequencydomain resource for all of the plurality of candidate TBS values. Insome embodiments, the frequency domain resource is indicated by the ULgrant.

In above embodiments, X_(i) is used as a TBS value. Alternative, X_(i)may indicate a TBS index. Also, the embodiments above with respect tothe TBS value may be applied to the TBS index. In this case, the TBSvalue may be determined by the indicated number of PRBs/RUs and thecorresponding TBS index X_(i).

Method to Indicate PRB/RU Allocations for Different TBS Values

In some embodiments, the UE may determine the number of resourceallocation units for Msg3 with EDT based on a resource assignment fieldin the UL grant, as the legacy random access procedure without EDT. Inthe eMTC system, the resource assignment field may include the PRBassignment field. In the NB-IoT system, the resource assignment fieldmay include the RU assignment field. Similarly, the indication method ofMsg3 subcarrier allocation for EDT may be the same as legacy NB-IoTMsg3.

Alternatively, in some embodiments, the UE may determine the number ofresource allocation units for Msg3 with EDT based on the MCS/TBSindication field in the UL grant. In some embodiments, the number ofresource allocation units may be determined based on a plurality ofstates indicated by the MCS/TBS indication field, in particularly forthe NB-IoT system.

In some embodiments, the reserved bit ‘R’ in the RAR may be used todifferentiate the UL grant for legacy Msg3 scheduling and that for Msg3scheduling with EDT. In this case, the 8 states indicated by the 3-bitMCS/TBS indication field may be used to indicate the modulation schemeand/or coding scheme and the number of resource allocation units forEDT.

In some embodiments, the modulation scheme may include pi/2 binary phaseshift keying (BPSK) and pi/4 quadrature phase shift keying (QPSK) whenthe Msg3 is transmitted with a single-tone mode. In some embodiments,selection of the pi/2 BPSK and the pi/4 QPSK may be based on TBS valuesand the number of resource allocation units. In some embodiments, pi/2BPSK may be used when the TBS value is equal to 328 and the number ofresource allocation units is equal to 8 or 10; otherwise pi/4 QPSK maybe used. In some embodiments, the pi/4 QPSK is used for the Msg3transmitted with the single-tone mode irrespective of TBS values and thenumber of resource allocation units. In some embodiments, QPSK is usedwhen the Msg3 is transmitted with a multi-tone mode. In someembodiments, the number of RUs may be any value from set {1, 2, 3, 4, 5,6, 8, 10}.

In an embodiment, a common table may be designed for all 8 possiblemaximum TBS values, e.g. as shown in Table 6. Alternatively, in anotherembodiment, different tables may be designed for different maximum TBSvalues. For example, Table 6 is designed for cases where the maximum TBSvalue broadcasted is small (e.g. 4 smaller candidate TBS valuesaccordingly) and Table 7 is designed for cases where the maximum TBSvalue broadcasted is large (e.g. 4 larger candidate TBS valuesaccordingly). In yet another example, one or more tables (e.g., Table 6and Table 7) may be defined, and explicit indication may be used todetermine which table to be used via e.g. higher layer signaling (e.g.,RRC signaling). The configuration of the table(s) may be independent ofthe configuration of the maximum TBS value.

TABLE 6 Example of MCS index for modulation scheme and the number ofresource allocation units for EDT MCS Modulation Modulation Number IndexΔf = 3.75 kHz or Δf = 15 kHz Δf = 15 kHz and of RUs I_(MCS) and I_(sc) =0, 1, . . . , 11 I_(sc) > 11 N_(RU) ‘000’ pi/2 BPSK QPSK 8 ‘001’ pi/2BPSK QPSK 6 ‘010’ pi/2 BPSK QPSK 4 ‘011’ pi/4 QPSK QPSK 8 ‘100’ pi/4QPSK QPSK 6 ‘101’ pi/4 QPSK QPSK 4 ‘110’ pi/4 QPSK QPSK 3 ‘111’ pi/4QPSK QPSK 1

TABLE 7 Example of MCS index for modulation scheme and the number ofresource allocation units for EDT MCS Modulation Modulation Number IndexΔf = 3.75 kHz or Δf = 15 kHz Δf = 15 kHz and of RUs I_(MCS) and I_(sc) =0, 1, . . . , 11 I_(sc) > 11 N_(RU) ‘000’ pi/2 BPSK QPSK 8 ‘001’ pi/4QPSK QPSK 8 ‘010’ pi/4 QPSK QPSK 6 ‘011’ pi/4 QPSK QPSK 5 ‘100’ pi/4QPSK QPSK 4 ‘101’ pi/4 QPSK QPSK 3 ‘110’ pi/4 QPSK QPSK 2 ‘111’ pi/4QPSK QPSK 1

In some embodiments, no reserved bit ‘R’ in the RAR is used todifferentiate the UL grant for legacy Msg3 scheduling and that for Msg3scheduling with EDT. The 5 reserved states indicated by the MCS/TBSindication field may be used. Similar to the above embodiments, a commontable may be designed for all 8 possible maximum values, e.g. as givenby Table 7 where the first 3 rows are the same as that in the legacyNB-IoT system. Alternatively, different tables may be designed fordifferent maximum TBS values. For example, Table 7 is designed for caseswhere the maximum TBS value broadcasted is small, and Table 8 isdesigned for cases where the maximum TBS value broadcasted is large. Inan embodiment, one or more tables (e.g., Table 7 and Table 8) may bedefined, and explicit indication may be used to determine which table tobe used via e.g. RRC signaling. The configuration of the table(s) may beindependent of the configuration of the maximum TBS value.

TABLE 8 Example of MCS index for modulation scheme and the number ofresource MCS Modulation Modulation Number Index Δf = 3.75 kHz or Δf = 15kHz Δf = 15 kHz and of RUs I_(MCS) and I_(sc) = 0, 1, . . . , 11I_(sc) > 11 N_(RU) ‘000’ pi/2 BPSK QPSK 4 ‘001’ pi/4 QPSK QPSK 3 ‘010’pi/4 QPSK QPSK 1 ‘011’ pi/2 BPSK QPSK 8 ‘100’ pi/2 BPSK QPSK 6 ‘101’pi/4 QPSK QPSK 8 ‘110’ pi/4 QPSK QPSK 4 ‘111’ pi/4 QPSK QPSK 1allocation units for EDT

TABLE 9 Example of MCS index for modulation scheme and the number ofresource allocation units for EDT MCS Modulation Modulation Number IndexΔf = 3.75 kHz or Δf = 15 kHz Δf = 15 kHz of RUs I_(MCS) and I_(sc) = 0,1, . . . , 11 and I_(sc) > 11 N_(RU) ‘000’ pi/2 BPSK QPSK 4 ‘001’ pi/4QPSK QPSK 3 ‘010’ pi/4 QPSK QPSK 1 ‘011’ pi/2 BPSK QPSK 8 ‘100’ pi/4QPSK QPSK 8 ‘101’ pi/4 QPSK QPSK 6 ‘110’ pi/4 QPSK QPSK 4 ‘111’ pi/4QPSK QPSK 1

In above embodiments, Table 5, Table 6, Table 7 and Table 8 areillustrated to provide some examples. The embodiments are not limited inthis respect. Other combinations of modulation scheme and/or codingscheme and number of PRBs/RUs/subcarriers are possible. Even thoughexamples of coding rates are not illustrated in the tables above, theMCS/TBS indication field may also be used to indicate coding schemes.

Indication of the number of resource allocation units is describedabove. In some embodiment, the indication of the number of resourceallocation units above may be used for all of a plurality of candidateTBS values available to the UE.

Alternatively, in some embodiment, the indication of the number ofresource allocation units above may be only used for a first candidateTBS value of a plurality of candidate TBS values available to the UE. Inan embodiment, the first candidate TBS value is the largest one amongthe plurality of candidate TBS values, i.e., X₀ as above. Determinationof the number of resource allocation units for other candidate TBSvalues will be described below.

In some embodiments, the number of resource allocation units for asecond candidate TBS value of the plurality of candidate TBS values maybe determined based on a mapping between the first candidate TBS valueand the second candidate TBS value. For example, when the TBS value orindex X₂ and/or X₃ is no more than ½*X₀, the number ofPRBs/RUs/subcarriers assigned for X₂ and/or X₃ may be the largest valuewithin the set {1, 2, 3, 4, 5, 6, 8, 10} which is smaller than thatindicated for X₀, or may be the largest value within the set {1, 2, 3,4, 5, 6, 8, 10} which is no more than half of the number ofPRBs/RUs/subcarriers indicated for X₀.

In some embodiments, in the NB-IoT system, in cases where the number ofRUs for X₀ is not indicated by the UL grant in the RAR, e.g. the numberof RUs for X₀ is semi-statically configured or predefined in spec, or incases where less than 3 bits are used for the indication of number ofRUs for X₀, N bits out of 3 bits in the MCS/TBS indication field or thereserved states in this field may be used for indication of the numberof RUs for X₁, X₂ and/or X₃. In cases where the smaller number of RUsare allocated only for X₂ and/or X₃, the allocated number of RUs forother candidate TBS value(s) (e.g. X₁) would follow that for X₀. Forexample, the reserved bit ‘R’ in RAR may be used to indicate whether theUL grant is for EDT or not, 2 bits may be used to indicate modulationscheme and number of RUs for X₀, and remaining 1 bit in the MCS/TBSindication field may be used to indicate whether a smaller number of RUsto be used for the candidate TBS values smaller than X₀, e.g. for X₂and/or X₃. As another example, no reserved bit ‘R’ is used, while 5reserved states may be used to indicate the combination of number of RUsfor X₀ and whether a predefined smaller number of RUs to be allocatedfor other candidate TBS values.

In some embodiments, in the eMTC system, the MCS/TBS indication fieldmay be used to indicate the number of PRBs for other candidate TBSvalues, for example, in cases where the number of RUs for X₀ is notindicated by the UL grant in the RAR. For example, N bits out of 3 bitsin CE mode A and M bits out of 2 bits in CE mode B may be used toindicate the number of PRBs allocated for the candidate TBS values otherthan X₀. In one example, N and M may be equal to 1 to indicate whether apredefined smaller number of PRBs (e.g. the PRBs allocated for X₀ exceptending K PRBs, e.g. K=1 or 2) to be allocated for X₁, X₂ and/or X₃. Incases where the smaller number of PRBs are allocated only for X₂ and/orX₃, the number of PRBs for other candidate TBS values (e.g. X₁) wouldfollow that for X₀.

Method to Indicate the Number of Repetitions for Different TBS Values

In some embodiments, the number of repetitions for Msg3 with EDT may beindicated by the repetition number field in the UL grant in RAR as inlegacy eMTC/NB-IoT systems. In some embodiments, the same number ofrepetitions may be used for all candidate TBSs to be selected by the UE.Alternatively, in some embodiments, the number of repetitions for Msg3with EDT may be different for different candidate TBS values.

In some embodiments, the number of repetitions for Msg3 with EDTindicated by the repetition number field may be determined as that forthe largest candidate TBS value X₀ of the plurality of candidate TBSvalues. In some embodiments, the number of repetitions for anothercandidate TBS value of the plurality of candidate TBS values may bedetermined based on a mapping between the number of repetitions for thelargest candidate TBS value and the number of repetitions for theanother candidate TBS value. For example, when the TBS value or index X₂and/or X₃ is no more than ½*X₀, the number of repetitions assigned forX₂ and/or X₃ may be the largest value within a set of supportedrepetition numbers that is smaller than the number of repetitionsindicated for X₀. Alternatively, RRC signaling may be used to indicatethe number of repetitions for certain TBS values or indexes. Forexample, the mapping (e.g. a scaling factor) from the number ofrepetitions for the largest candidate TBS value to the number ofrepetitions for other smaller candidate TBS values may be indicated bye.g., the RRC signaling.

In some embodiments, the number of repetitions (or scaling factors) forthe candidate TBS values is determined based on the maximum TBS valueconfigured by the AN. For a certain maximum TBS value, there is amapping between the number of repetitions indicated by the repetitionnumber field and each of the plurality of candidate TBS values. In anembodiment, the mapping may include one or more sets of scaling factorsfor the number of repetitions for the plurality of candidate TBS valuewith respect to the number of repetitions indicated by the repetitionnumber field. For example, the scaling factors may be selected from {⅜,½, ⅝, ¾, ⅞, 1}. Table 10 and Table 11 provide some examples of the setof scaling factors for the eMTC system and the NB-IoT system,respectively. For example, X₀>X₁>X₂>X₃, and they correspond to the up tofour candidate TBS values. Other mappings from the maximum TBS value todifferent sets of scaling factors are possible. The embodiments are notlimited in this respect.

TABLE 10 Example of sets of scaling factor for number of repetitionscorresponding to maximum Max Set 1 of scaling factors Set 2 of scalingfactors TBS for X₃, X₂, X₁, X₀ for X₃, X₂, X₁, X₀ 328 {1} {1} 408 {⅞, 1}{¾, 1} 456 {¾, 1, 1} {¾, ⅞, 1} 504 {¾, ⅞, 1, 1} {⅝, ¾, ⅞, 1} 600 {⅝, ¾,⅞, 1} {½, ⅝, ⅞, 1} 712 {½, ¾, ⅞, 1} {½, ⅝, ⅞, 1} 808 {½, ⅝, 1, 1} {⅜, ⅝,⅞, 1} 936 {⅜, ⅝, ⅞, 1} {⅜, ½, ¾, 1} 1000 {⅜, ⅝, ⅞, 1} {⅜, ½, ¾, 1}

TABLE 11 Example of sets of scaling factor for number of repetitionscorresponding to maximum TBS value for NB-IoT TBS value for eMTC Max Setof scaling factors TBS for X₃, X₂, X₁, X₀ 328 {1} 408 {⅞, 1} 504 {¾, ⅞,1} 584 {⅝, ¾, ⅞, 1} 680 {½, ¾, ⅞, 1} 808 {½, ⅝, ⅞, 1} 936 {⅜, ⅝, ⅞, 1}1000 {⅜, ⅝, ⅞, 1}

In some embodiments, more than one sets of scaling factors areconfigured for a certain maximum TBS value, then which set of scalingfactors to be used is indicated by higher layer signaling or the ULgrant, e.g., the MCS/TBS indication field (in particular for the eMTCsystem). In some embodiments, only one set of scaling factors ispredefined for a certain maximum TBS value. In some embodiments, morethan one sets of scaling factors are configured for a certain maximumTBS value, then which set of scaling factors to be used is indicated byhigher layer signaling or the UL grant, e.g., the MCS/TBS indicationfield (in particular for the eMTC system). In some embodiments, only oneset of scaling factors is predefined for a certain maximum TBS value.For example, the scaling factor for one of candidate TBS values isdenoted by α, the number of repetitions used for the candidate TBS valuemay be calculated by ceil(α*R). Here, R is the number of repetitionsindicated by the UL grant. Alternatively, the number of repetitions maybe a value selected from a predefined set, which is closest toceil(α*R). For example, the predefined set may be the same as the numberof repetitions supported in legacy eMTC/NB-IoT systems, e.g. {1, 2, 4,8, 16, 32, 64, 128, 192, 256, 384, 512, 768, 1024, 1536, 2048} for theeMTC system and {1, 2, 4, 8, 16, 32, 64, 128} for the NB-IoT system. Inan embodiment, all values which are multiples of 4 or 8 may be includedin the predefined set. For example, the number of repetitions may becalculated by ceil(α*R/x)*x. Here, x may be any integer such as 4 or 8.For another example, the number of repetitions may be calculated by

$\left\{ {{{\begin{matrix}{1,{{{{if}\mspace{14mu}\alpha*R} \leq 1};}} \\{2,{{{if}\mspace{14mu} 1} < {\alpha*R} \leq 2}} \\{{{{ceil}\left( {\alpha*{R/4}} \right)}*4},{otherwise}}\end{matrix}{with}\mspace{14mu} x} = 4},{{or}\left\{ {{\begin{matrix}{1,{{{{if}\mspace{14mu}\alpha*R} \leq 1};}} \\{2,{{{if}\mspace{14mu} 1} < {\alpha*R} \leq 2}} \\{4,{{{if}\mspace{14mu} 2} < {\alpha*R} \leq 4}} \\{{{{ceil}\left( {\alpha*{R/8}} \right)}*8},{otherwise}}\end{matrix}{with}\mspace{14mu} x} = 8.} \right.}} \right.$

In an embodiment, the maximum TBS value is used as the largest candidateTBS value X₀ and the selected TBS value is X_(i), then the scalingfactors may be X_(i)/X₀. As repetitions helps improve the receivedsignal noise ratio (SNR), in another embodiment, the scaling factors maybe log(X_(i)/X₀). Other scaling factors are possible. The embodimentsare not limited in this respect.

In some embodiments, the smaller candidate TBS values (e.g., X₁, X₂and/or X₃) may be determined based on a portion of bits in the MCS/TBSindication field of the UL grant or a portion of states indicated by theMCS/TBS indication field. For example, N bits out of 3 bits in CE mode Aand M bits out of 2 bits in CE mode B may be used to indicate the numberof repetitions allocated for the smaller candidate TBS values (e.g., X₁,X₂ and/or X₃). In one example, N and/or M may be equal to 1, that is,one bit in the MCS/TBS indication field indicates whether a predefinedsmaller number of repetitions (e.g. the largest supported number ofrepetitions that is smaller than the number of repetitions indicated bythe UL grant or the number of repetitions configured by RRC signalingfor smaller candidate TBS values) to be allocated for X₁, X₂ and/or X₃.In cases the smaller number of repetitions are allocated only for X₂and/or X₃, the number of repetitions for other candidate TBS(s) (e.g.X₁) would follow the number of repetitions for X₀.

Indication of Selected TBS Among the Up to 4 Possible Values

The UE may determine a plurality of candidate TBS values to be selectedby the UE, as mentioned above. The AN needs to blindly detect which TBSamong the e.g., up to 4 candidate TBS values is selected by the UE. Ifan initial transmission of the Msg3 is not detected successfully, the ANmay still reserve the same amount of resources for retransmission of theMsg3, even though the number of repetitions needed may be smaller thanthe indicated one when the UE selects a smaller TBS. Thus, the resourcesnot used by the retransmission would be wasted. To resolve this issue,indication for selected TBS, which is independently detectable fromactual data transmission, is supported. How to inform the AN about thetarget TBS value selected by the UE will be described below.

In some embodiments, an indicator configured to indicate a target TBSvalue selected by the UE may be included in the Msg3 with EDT. Theindicator may include one or more bits. In an embodiment, the indicatorincludes two bits. Alternatively, in an embodiment, the number of bitsfor the indicator depends on the maximum TBS value, for example, 1 or 2bits may be supported. For example, 1 bit is used when the maximum TBSvalue is no more than 408 bits, while 2 bits are used for other cases.As another example, 1 bit is always used for the NB-IoT system, as thesupported number of repetitions that can be scheduled by the UL grant isrestricted to set {1, 2, 4, 8, 16, 32, 64, 128} and 1 bit is sufficientto indicate whether the selected TBS value is no more than ½ of themaximum TBS value.

In some embodiments, the indicator is piggybacked following uplinkcontrol information (UCI) on PUSCH, as the legacy LTE system. Themapping for the indicator may follow the resource element mapping forHARQ-ACK information, or channel status information (CSI) information orscheduling request (SR) information.

In some embodiments, the indicator may be carried only in the initialtransmission of the Msg3. In an embodiment, the indicator is carried infirst M subframes for the initial transmission. M is a positive integer,for example, the indicator may be carried only in the first onesubframe. M may be determined based on at least one of predefinition,higher layer signaling (e.g., the RRC signaling), the number ofrepetitions of the initial transmission indicated by the AN (e.g., amapping from the number of repetitions of the initial transmissionindicated by the AN), a maximum TBS value configured by the AN, and thenumber of subframes for the maximum TBS value. For example, M may bedetermined by ceil(β*T), where β depends on the maximum TBS value and Tis the number of subframes indicated by the UL grant for the maximum TBSvalue. The transmission mechanism may follow PUCCH for the eMTC systemand NPUSCH format 2 for the NB-IoT system. For the NB-IoT system, the Msubframes may be multiple of RUs where RU may reuse the concept definedfor NPUSCH format 2 in Rel-13 NB-IoT.

Alternatively, in some embodiments, the indicator may be carried in eachof the initial transmission of the Msg3 and one or more of repetitionsof the initial transmission. In an embodiment, the indicator may becarried in first one or more repetitions. In an embodiment, theindicator may be carried in first M subframes for each of the initialtransmission and the one or more repetitions. M is a positive integerand may be determined as above. The number of the one or morerepetitions to carry the indicator is determined based on at least oneof predefinition, higher layer signaling (e.g., the RRC signaling), thenumber of repetitions of the initial transmission to be used for thesmallest TBS value available to the UE, a maximum TBS value configuredby the AN, and the number of repetitions of the initial transmissionindicated by the AN. In an example, the number of repetitions to carrythe indicator is based on a mapping from the indicated number ofrepetitions indicated by the UL grant. In an example, the number ofrepetitions to carry the indicator may be equal to the number ofrepetitions to be used for the smallest candidate TBS value selectableto the UE. In an example, the number of repetitions to carry theindicator may be determined by ceil(β*R), where β is based on themaximum TBS value and R is the number of repetitions indicated by the ULgrant.

In some embodiments, the indicator may be carried in first one or moresymbols within each of one or more subframes. In some embodiments, theone or more subframes may include a subframe for a repetition of theinitial transmission of the Msg3. In other words, the indicator may becarried in one or more symbols for the initial transmission only, in oneor more symbols for one or more repetition of the initial transmissiononly, or in one or more symbols for both.

In some embodiments, the frequency domain resources used for theindicator transmission may be the same as that used for other datatransmission. Either time-first or frequency first mapping may be usedfor the resource element mapping for the indicator. If time-firstmapping is used, the bits of indicator are mapped to up to the one ormore symbols used to carry the indicator one subcarrier by onesubcarrier.

In some embodiments, the indicator may be carried in a demodulationreference signal (DMRS). For example, a phase may be added to the DMRSsymbols. For a 1-bit indicator, DMRS may be multiplied by −1 or 1 tocarry the 1-bit indicator.

In some embodiments, if the AN fails to detect the indicator for theselected TBS value, the AN may still allocate the same amount ofresources for a retransmission as that for the initial transmission.

In some cases, the indicator is detected incorrectly and allocatedresources by the AN for the retransmission are different from that usedby the UE for the initial transmission. In an embodiment, the UE mayfollow the resource allocation indicated by the UL grant scheduling theretransmission. In another embodiment, the UE may use the same amount ofresources for the retransmission as that for the initial transmission,when the amount of resources for the retransmission indicated by the ANis larger than the amount of resources used by the UE for the initialtransmission. For example, the number of repetitions used by the UE forinitial transmission is R₀, however, the AN incorrectly detects theselected TBS value and schedules the number of repetitions R₁ withR₀<R₁. In this case, the UE may still use R₀ repetitions for theretransmission. As another example, the AN may not be able to scheduleR₀ repetitions due to that R₀ does not belong to the set of supportednumber of repetitions that can be scheduled by the UL grant. In thiscase, the AN may schedule the number of repetitions that is larger thanR₀, and may assume that UE would use R₀ repetitions instead of thescheduled one based on the detected indicator.

Below, two embodiments are provided to illustrate design of EDT of thepresent disclosure.

In an embodiment for an eMTC system, the reserved bit ‘R’ is used toindicate whether the UL grant is for scheduling of legacy Msg3 withoutEDT or Msg3 with EDT. When the UL grant is used for scheduling of EDT,the frequency domain resource allocation is indicated by the UL grant asin legacy eMTC, which is used for all candidate TBS values.

The largest candidate TBS value among the up to 4 candidate TBS valuesmay be determined by the largest one of a plurality of TBS valuescorresponding to the allocated number of PRBs in Table 7.1.7.2.1-1 in36.213. The determined largest candidate TBS value is no more than themaximum TBS value broadcasted by the system information. For the otherup to three candidate TBS values, a predefined mapping from the largestcandidate TBS value may be defined. For example, denoting the TBS indexfor the largest candidate TBS value by I₀, the other up to threecandidate TBS indices may be obtained by ceil(I₀*¾), ceil(I₀/2) and/orceil(I₀/4) whichever provide the candidate TBS values larger than theminimum TBS values supported for EDT (which is about 320 bits as agreedin RAN2).

The modulation scheme and/or coding rate may be determined according tothe TBS index, by reading the MCS index table defined in a legacy eMTC.

For the number of repetitions, the number of repetitions indicated bythe UL grant as in legacy eMTC may be assigned for the largest candidateTBS value among the up to 4 candidate TBS values. N bit(s) out of 3 bitsin the MCS/TBS indication field for CE mode A and M bit(s) out of 2 bitsin the MCS/TBS indication field for CE mode B may be used to indicatethe number of repetitions for other smaller candidate TBS values. Forexample, 1 bit may be used to indicate whether the number of repetitionsfor the smallest one or two candidate TBS values may be the valuesmaller than the number of repetitions indicated for the largestcandidate TBS value. For example, in cases where there are 4 candidateTBS values to be selected by the UE, the 1 bit may be used to indicatewhether the number of repetitions smaller than the value indicated forlargest candidate TBS value may be allocated for the smallest twocandidate TBS values. As another example, in cases where there are 2 or3 candidate TBS values to be selected by the UE, the 1 bit may be usedto indicate whether the number of repetitions smaller than the valueindicated for the largest candidate TBS value may be allocated for thesmallest candidate TBS value. Alternatively, 2 bits may be used toindicate whether the smaller number of repetitions may be used for thefollowing cases: the other up to 3 smaller candidate TBS values, thesmallest 2 candidate TBS values, the smallest candidate TBS value, ornot be used for all candidate TBS values. The smaller number ofrepetitions may be the largest one within the set of supportedrepetition numbers that is smaller than the value for the maximum TBSvalue.

In another embodiment for a NB-IoT system, no reserved bit is used. The5 reserved states in the MCS/TBS indication field may be used todifferentiate the UL grant for scheduling of Msg3 with EDT and Msg3without EDT.

When the UL grant is used for scheduling of EDT, the subcarrierallocation is indicated by the UL grant as in a legacy NB-IoT, which maybe used for all candidate TBS values.

The number of RUs is indicated by the MCS/TBS indication field in ULgrant, using the 5 reserved states. K out of 5 states may be used toindicate that the number of RUs for other smaller candidate TBS valuesare smaller than the number of RUs assigned for the largest candidateTBS value. For example, 3 states may be defined to indicate 3 possiblenumber of RUs, which applies to all candidate TBS values. The other 2states may be defined to indicate relatively large number of RUs whichonly applies to certain candidate TBS values (e.g. X₀ and X₁). Thenumber of RUs for other candidate TBS values (e.g. X₂ and X₃) may be thelargest values within the set {1, 2, 3, 4, 5, 6, 8, 10} each of which issmaller than the indicated number of RUs for maximum TBS value.

The largest candidate TBS value among the up to 4 candidate TBS valuesmay be determined by the largest one of a plurality of TBS valuescorresponding to the allocated number of RUs in Table 16.5.1.2-2 in36.213 which is no more than the maximum TBS value broadcasted by thesystem information. For the other up to three candidate TBS values, apredefined mapping from the largest candidate TBS value may be defined.For example, denoting the TBS index for the largest candidate TBS valueby I₀, the other up to three TBS indices may be obtained by ceil(I₀*¾),ceil(I₀/2) and/or ceil(I₀/4) whichever provide the TBS values largerthan the minimum TBS values supported for EDT (which is about 320 bitsas agreed in RAN2).

The modulation/coding scheme may be determined according to the TBSindex, by reading the MCS index table defined in legacy NPUSCH (e.g.table 16.5.1.2-1 in 36.213 can be used when single-tone Msg3 isscheduled while QPSK is used when multi-tone Msg3 is scheduled).Alternatively, for single-tone Msg3, pi/2-BPSK is used when TBS of 328bits and RU index of 6 or 7 (i.e., 8 or 10 RUs) are selected, whilepi/4-QPSK is used for other single-tone Msg3 transmission. As anotherexample, pi/2-BPSK is used when TBS of 328 bits and RU index of 6 or 7,or TBS of 408 bits and RU index of 6 are selected, while pi/4-QPSK isused for other single-tone Msg3 transmission. In yet another example,only pi/4-QPSK is used for single-tone Msg3 transmission with EDT.

The number of repetitions indicated by the UL grant as in the legacyNB-IoT. The same number of repetitions may be used for all candidate TBSvalues.

The two embodiments above are only for purpose of illustration, but notlimitation. The features of the two embodiments may be combined withthose in any other embodiments of the present disclosure. Theembodiments are not limited in this respect.

FIG. 3 illustrates example components of a device 300 in accordance withsome embodiments. In some embodiments, the device 300 may includeapplication circuitry 302, baseband circuitry 304, Radio Frequency (RF)circuitry 306, front-end module (FEM) circuitry 308, one or moreantennas 310, and power management circuitry (PMC) 312 coupled togetherat least as shown. The components of the illustrated device 300 may beincluded in a UE or an AN. In some embodiments, the device 300 mayinclude less elements (e.g., an AN may not utilize application circuitry302, and instead include a processor/controller to process IP datareceived from an EPC). In some embodiments, the device 300 may includeadditional elements such as, for example, memory/storage, display,camera, sensor, or input/output (I/O) interface. In other embodiments,the components described below may be included in more than one device(e.g., said circuitries may be separately included in more than onedevice for Cloud-RAN (C-RAN) implementations).

The application circuitry 302 may include one or more applicationprocessors. For example, the application circuitry 302 may includecircuitry such as, but not limited to, one or more single-core ormulti-core processors. The processor(s) may include any combination ofgeneral-purpose processors and dedicated processors (e.g., graphicsprocessors, application processors, etc.). The processors may be coupledwith or may include memory/storage and may be configured to executeinstructions stored in the memory/storage to enable various applicationsor operating systems to run on the device 300. In some embodiments,processors of application circuitry 302 may process IP data packetsreceived from an EPC.

The baseband circuitry 304 may include circuitry such as, but notlimited to, one or more single-core or multi-core processors. Thebaseband circuitry 304 may include one or more baseband processors orcontrol logic to process baseband signals received from a receive signalpath of the RF circuitry 306 and to generate baseband signals for atransmit signal path of the RF circuitry 306. Baseband processingcircuitry 304 may interface with the application circuitry 302 forgeneration and processing of the baseband signals and for controllingoperations of the RF circuitry 306. For example, in some embodiments,the baseband circuitry 304 may include a third generation (3G) basebandprocessor 304A, a fourth generation (4G) baseband processor 304B, afifth generation (5G) baseband processor 304C, or other basebandprocessor(s) 304D for other existing generations, generations indevelopment or to be developed in the future (e.g., second generation(2G), sixth generation (6G), etc.). The baseband circuitry 304 (e.g.,one or more of baseband processors 304A-D) may handle various radiocontrol functions that enable communication with one or more radionetworks via the RF circuitry 306. In other embodiments, some or all ofthe functionality of baseband processors 304A-D may be included inmodules stored in the memory 304G and executed via a Central ProcessingUnit (CPU) 304E. The radio control functions may include, but are notlimited to, signal modulation/demodulation, encoding/decoding, radiofrequency shifting, etc. In some embodiments, modulation/demodulationcircuitry of the baseband circuitry 304 may include Fast-FourierTransform (FFT), precoding, or constellation mapping/demappingfunctionality. In some embodiments, encoding/decoding circuitry of thebaseband circuitry 304 may include convolution, tail-biting convolution,turbo, Viterbi, or Low Density Parity Check (LDPC) encoder/decoderfunctionality. Embodiments of modulation/demodulation andencoder/decoder functionality are not limited to these examples and mayinclude other suitable functionality in other embodiments.

In some embodiments, the baseband circuitry 304 may include one or moreaudio digital signal processor(s) (DSP) 304F. The audio DSP(s) 304F mayinclude elements for compression/decompression and echo cancellation andmay include other suitable processing elements in other embodiments.Components of the baseband circuitry may be suitably combined in asingle chip, a single chipset, or disposed on a same circuit board insome embodiments. In some embodiments, some or all of the constituentcomponents of the baseband circuitry 304 and the application circuitry302 may be implemented together such as, for example, on a system on achip (SOC).

In some embodiments, the baseband circuitry 304 may provide forcommunication compatible with one or more radio technologies. Forexample, in some embodiments, the baseband circuitry 304 may supportcommunication with an evolved universal terrestrial radio access network(EUTRAN) or other wireless metropolitan area networks (WMAN), a wirelesslocal area network (WLAN), a wireless personal area network (WPAN).Embodiments in which the baseband circuitry 304 is configured to supportradio communications of more than one wireless protocol may be referredto as multi-mode baseband circuitry.

RF circuitry 306 may enable communication with wireless networks usingmodulated electromagnetic radiation through a non-solid medium. Invarious embodiments, the RF circuitry 306 may include switches, filters,amplifiers, etc. to facilitate the communication with the wirelessnetwork. RF circuitry 306 may include a receive signal path which mayinclude circuitry to down-convert RF signals received from the FEMcircuitry 308 and provide baseband signals to the baseband circuitry304. RF circuitry 306 may also include a transmit signal path which mayinclude circuitry to up-convert baseband signals provided by thebaseband circuitry 304 and provide RF output signals to the FEMcircuitry 308 for transmission.

In some embodiments, the receive signal path of the RF circuitry 306 mayinclude mixer circuitry 306 a, amplifier circuitry 306 b and filtercircuitry 306 c. In some embodiments, the transmit signal path of the RFcircuitry 306 may include filter circuitry 306 c and mixer circuitry 306a. RF circuitry 306 may also include synthesizer circuitry 306 d forsynthesizing a frequency for use by the mixer circuitry 306 a of thereceive signal path and the transmit signal path. In some embodiments,the mixer circuitry 306 a of the receive signal path may be configuredto down-convert RF signals received from the FEM circuitry 308 based onthe synthesized frequency provided by synthesizer circuitry 306 d. Theamplifier circuitry 306 b may be configured to amplify thedown-converted signals and the filter circuitry 306 c may be a low-passfilter (LPF) or band-pass filter (BPF) configured to remove unwantedsignals from the down-converted signals to generate output basebandsignals. Output baseband signals may be provided to the basebandcircuitry 304 for further processing. In some embodiments, the outputbaseband signals may be zero-frequency baseband signals, although thisis not a requirement. In some embodiments, mixer circuitry 306 a of thereceive signal path may comprise passive mixers, although the scope ofthe embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 306 a of the transmit signalpath may be configured to up-convert input baseband signals based on thesynthesized frequency provided by the synthesizer circuitry 306 d togenerate RF output signals for the FEM circuitry 308. The basebandsignals may be provided by the baseband circuitry 304 and may befiltered by filter circuitry 306 c.

In some embodiments, the mixer circuitry 306 a of the receive signalpath and the mixer circuitry 306 a of the transmit signal path mayinclude two or more mixers and may be arranged for quadraturedownconversion and upconversion, respectively. In some embodiments, themixer circuitry 306 a of the receive signal path and the mixer circuitry306 a of the transmit signal path may include two or more mixers and maybe arranged for image rejection (e.g., Hartley image rejection). In someembodiments, the mixer circuitry 306 a of the receive signal path andthe mixer circuitry 306 a may be arranged for direct downconversion anddirect upconversion, respectively. In some embodiments, the mixercircuitry 306 a of the receive signal path and the mixer circuitry 306 aof the transmit signal path may be configured for super-heterodyneoperation.

In some embodiments, the output baseband signals and the input basebandsignals may be analog baseband signals, although the scope of theembodiments is not limited in this respect. In some alternateembodiments, the output baseband signals and the input baseband signalsmay be digital baseband signals. In these alternate embodiments, the RFcircuitry 306 may include analog-to-digital converter (ADC) anddigital-to-analog converter (DAC) circuitry and the baseband circuitry304 may include a digital baseband interface to communicate with the RFcircuitry 306.

In some dual-mode embodiments, a separate radio IC circuitry may beprovided for processing signals for each spectrum, although the scope ofthe embodiments is not limited in this respect.

In some embodiments, the synthesizer circuitry 306 d may be afractional-N synthesizer or a fractional N/N+1 synthesizer, although thescope of the embodiments is not limited in this respect as other typesof frequency synthesizers may be suitable. For example, synthesizercircuitry 306 d may be a delta-sigma synthesizer, a frequencymultiplier, or a synthesizer comprising a phase-locked loop with afrequency divider.

The synthesizer circuitry 306 d may be configured to synthesize anoutput frequency for use by the mixer circuitry 306 a of the RFcircuitry 306 based on a frequency input and a divider control input. Insome embodiments, the synthesizer circuitry 306 d may be a fractionalN/N+1 synthesizer.

In some embodiments, frequency input may be provided by a voltagecontrolled oscillator (VCO), although that is not a requirement. Dividercontrol input may be provided by either the baseband circuitry 304 orthe applications processor 302 depending on the desired outputfrequency. In some embodiments, a divider control input (e.g., N) may bedetermined from a look-up table based on a channel indicated by theapplications processor 302.

Synthesizer circuitry 306 d of the RF circuitry 306 may include adivider, a delay-locked loop (DLL), a multiplexer and a phaseaccumulator. In some embodiments, the divider may be a dual modulusdivider (DMD) and the phase accumulator may be a digital phaseaccumulator (DPA). In some embodiments, the DMD may be configured todivide the input signal by either N or N+1 (e.g., based on a carry out)to provide a fractional division ratio. In some example embodiments, theDLL may include a set of cascaded, tunable, delay elements, a phasedetector, a charge pump and a D-type flip-flop. In these embodiments,the delay elements may be configured to break a VCO period up into Ndequal packets of phase, where Nd is the number of delay elements in thedelay line. In this way, the DLL provides negative feedback to helpensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuitry 306 d may be configured togenerate a carrier frequency as the output frequency, while in otherembodiments, the output frequency may be a multiple of the carrierfrequency (e.g., twice the carrier frequency, four times the carrierfrequency) and used in conjunction with quadrature generator and dividercircuitry to generate multiple signals at the carrier frequency withmultiple different phases with respect to each other. In someembodiments, the output frequency may be a LO frequency (fLO). In someembodiments, the RF circuitry 306 may include an IQ/polar converter.

FEM circuitry 308 may include a receive signal path which may includecircuitry configured to operate on RF signals received from one or moreantennas 310, amplify the received signals and provide the amplifiedversions of the received signals to the RF circuitry 306 for furtherprocessing. FEM circuitry 308 may also include a transmit signal pathwhich may include circuitry configured to amplify signals fortransmission provided by the RF circuitry 306 for transmission by one ormore of the one or more antennas 310. In various embodiments, theamplification through the transmit or receive signal paths may be donesolely in the RF circuitry 306, solely in the FEM 308, or in both the RFcircuitry 306 and the FEM 308.

In some embodiments, the FEM circuitry 308 may include a TX/RX switch toswitch between transmit mode and receive mode operation. The FEMcircuitry may include a receive signal path and a transmit signal path.The receive signal path of the FEM circuitry may include an LNA toamplify received RF signals and provide the amplified received RFsignals as an output (e.g., to the RF circuitry 306). The transmitsignal path of the FEM circuitry 308 may include a power amplifier (PA)to amplify input RF signals (e.g., provided by RF circuitry 306), andone or more filters to generate RF signals for subsequent transmission(e.g., by one or more of the one or more antennas 310).

In some embodiments, the PMC 312 may manage power provided to thebaseband circuitry 304. In particular, the PMC 312 may controlpower-source selection, voltage scaling, battery charging, or DC-to-DCconversion. The PMC 312 may often be included when the device 300 iscapable of being powered by a battery, for example, when the device isincluded in a UE. The PMC 312 may increase the power conversionefficiency while providing desirable implementation size and heatdissipation characteristics.

While FIG. 3 shows the PMC 312 coupled only with the baseband circuitry304. However, in other embodiments, the PMC 312 may be additionally oralternatively coupled with, and perform similar power managementoperations for, other components such as, but not limited to,application circuitry 302, RF circuitry 306, or FEM 308.

In some embodiments, the PMC 312 may control, or otherwise be part of,various power saving mechanisms of the device 300. For example, if thedevice 300 is in an RRC_Connected state, where it is still connected tothe RAN node as it expects to receive traffic shortly, then it may entera state known as Discontinuous Reception Mode (DRX) after a period ofinactivity. During this state, the device 300 may power down for briefintervals of time and thus save power.

If there is no data traffic activity for an extended period of time,then the device 300 may transition off to an RRC_Idle state, where itdisconnects from the network and does not perform operations such aschannel quality feedback, handover, etc. The device 300 goes into a verylow power state and it performs paging where again it periodically wakesup to listen to the network and then powers down again. The device 300may not receive data in this state, in order to receive data, it musttransition back to RRC_Connected state.

An additional power saving mode may allow a device to be unavailable tothe network for periods longer than a paging interval (ranging fromseconds to a few hours). During this time, the device is totallyunreachable to the network and may power down completely. Any data sentduring this time incurs a large delay and it is assumed the delay isacceptable.

Processors of the application circuitry 302 and processors of thebaseband circuitry 304 may be used to execute elements of one or moreinstances of a protocol stack. For example, processors of the basebandcircuitry 304, alone or in combination, may be used execute Layer 3,Layer 2, or Layer 1 functionality, while processors of the applicationcircuitry 304 may utilize data (e.g., packet data) received from theselayers and further execute Layer 4 functionality (e.g., transmissioncommunication protocol (TCP) and user datagram protocol (UDP) layers).As referred to herein, Layer 3 may comprise a radio resource control(RRC) layer. As referred to herein, Layer 2 may comprise a medium accesscontrol (MAC) layer, a radio link control (RLC) layer, and a packet dataconvergence protocol (PDCP) layer. As referred to herein, Layer 1 maycomprise a physical (PHY) layer of a UE/RAN node.

FIG. 4 illustrates example interfaces of baseband circuitry inaccordance with some embodiments. As discussed above, the basebandcircuitry 304 of FIG. 3 may comprise processors 304A-304E and a memory304G utilized by said processors. Each of the processors 304A-304E mayinclude a memory interface, 404A-404E, respectively, to send/receivedata to/from the memory 304G.

The baseband circuitry 304 may further include one or more interfaces tocommunicatively couple to other circuitries/devices, such as a memoryinterface 412 (e.g., an interface to send/receive data to/from memoryexternal to the baseband circuitry 304), an application circuitryinterface 414 (e.g., an interface to send/receive data to/from theapplication circuitry 302 of FIG. 3), an RF circuitry interface 416(e.g., an interface to send/receive data to/from RF circuitry 306 ofFIG. 3), a wireless hardware connectivity interface 418 (e.g., aninterface to send/receive data to/from Near Field Communication (NFC)components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi®components, and other communication components), and a power managementinterface 420 (e.g., an interface to send/receive power or controlsignals to/from the PMC 312.

FIG. 5 is a block diagram illustrating components, according to someexample embodiments, able to read instructions from a machine-readableor computer-readable medium (e.g., a non-transitory machine-readablestorage medium) and perform any one or more of the methodologiesdiscussed herein. Specifically, FIG. 5 shows a diagrammaticrepresentation of hardware resources 500 including one or moreprocessors (or processor cores) 510, one or more memory/storage devices520, and one or more communication resources 530, each of which may becommunicatively coupled via a bus 540. For embodiments where nodevirtualization (e.g., NFV) is utilized, a hypervisor 502 may be executedto provide an execution environment for one or more networkslices/sub-slices to utilize the hardware resources 500.

The processors 510 (e.g., a central processing unit (CPU), a reducedinstruction set computing (RISC) processor, a complex instruction setcomputing (CISC) processor, a graphics processing unit (GPU), a digitalsignal processor (DSP) such as a baseband processor, an applicationspecific integrated circuit (ASIC), a radio-frequency integrated circuit(RFIC), another processor, or any suitable combination thereof) mayinclude, for example, a processor 512 and a processor 514.

The memory/storage devices 520 may include main memory, disk storage, orany suitable combination thereof. The memory/storage devices 520 mayinclude, but are not limited to any type of volatile or non-volatilememory such as dynamic random access memory (DRAM), static random-accessmemory (SRAM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), Flashmemory, solid-state storage, etc.

The communication resources 530 may include interconnection or networkinterface components or other suitable devices to communicate with oneor more peripheral devices 504 or one or more databases 506 via anetwork 508. For example, the communication resources 530 may includewired communication components (e.g., for coupling via a UniversalSerial Bus (USB)), cellular communication components, NFC components,Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components,and other communication components.

Instructions 550 may comprise software, a program, an application, anapplet, an app, or other executable code for causing at least any of theprocessors 510 to perform any one or more of the methodologies discussedherein. The instructions 550 may reside, completely or partially, withinat least one of the processors 510 (e.g., within the processor's cachememory), the memory/storage devices 520, or any suitable combinationthereof. Furthermore, any portion of the instructions 550 may betransferred to the hardware resources 500 from any combination of theperipheral devices 504 or the databases 506. Accordingly, the memory ofprocessors 510, the memory/storage devices 520, the peripheral devices504, and the databases 506 are examples of computer-readable andmachine-readable media.

The following paragraphs describe examples of various embodiments.

Example 1 includes an apparatus for a user equipment (UE), comprising: aprocessor configured to: encode a physical random access channel (PRACH)sequence from a plurality of PRACH sequence for transmission via a PRACHto perform a random access procedure, wherein indication of support ofearly data transmission (EDT) that is transmitted during the randomaccess procedure is based on at least one of the plurality of PRACHsequences, higher layer signaling, PRACH resources, PRACH formats, and apayload from the UE; and send the PRACH sequence to a radio frequency(RF) interface; and the RF interface to receive the PRACH sequence fromthe processor.

Example 2 includes the apparatus of Example 1, wherein the EDT comprisesuplink (UL) transmission and downlink (DL) transmission.

Example 3 includes the apparatus of Example 1, wherein the higher layersignaling comprises at least one of a system information (SI) messageand dedicated higher layer signaling.

Example 4 includes the apparatus of Example 1, wherein the EDT isenabled based on coverage enhancement (CE) levels.

Example 5 includes the apparatus of Example 1, wherein the PRACHresources are divided into different partitions, and one or morepartitions of the PRACH resources are configured to support the EDT.

Example 6 includes the apparatus of Example 5, wherein the PRACHresources comprise at least one of time resources and frequencyresources.

Example 7 includes the apparatus of Example 6, wherein differentfrequency hopping patterns are configured for different partitions ofthe PRACH resources.

Example 8 includes the apparatus of Example 1, wherein the plurality ofPRACH sequences are divided into different partitions, and one or morepartitions of the plurality of PRACH sequences are configured to supportthe EDT.

Example 9 includes the apparatus of Example 8, wherein the partitions ofthe plurality of PRACH sequences are divided based on at least one ofroot indexes and cyclic shifts.

Example 10 includes the apparatus of Example 5 or 8, wherein a number ofthe partitions of the PRACH resources or a number of the plurality ofPRACH sequences is configured to indicate support and/or requirement ofmultiple transport block size (TBS) values for the EDT.

Example 11 includes the apparatus of Example 5 or 8, wherein thepartitions of the PRACH resources or the plurality of PRACH sequencesare further divided for different CE levels.

Example 12 includes the apparatus of Example 5 or 8, wherein thepartitions of the PRACH resources or PRACH sequences are further dividedfor UL transmission and DL transmission of the EDT separately or forboth of the UL transmission and the DL transmission of the EDT.

Example 13 includes the apparatus of Example 1, wherein the PRACHformats comprises single-tone PRACH and multi-tone PRACH.

Example 14 includes the apparatus of Example 1, wherein the payload fromthe UE is transmitted following the PRACH sequence to indicate whetherthe UE supports the EDT or not.

Example 15 includes the apparatus of Example 1, wherein the payload isfurther configured to indicate a desired TBS value for UL transmissionof the EDT.

Example 16 includes an apparatus for a user equipment (UE), comprising:a radio frequency (RF) interface to receive a random access response(RAR) from an access node; and a processor configured to: receive theRAR from the RF interface; decode the RAR to obtain an uplink (UL)grant; and determine whether the UL grant is used for scheduling ofearly data transmission (EDT) that is transmitted during a random accessprocedure.

Example 17 includes the apparatus of Example 16, wherein whether the ULgrant is used for scheduling of EDT is determined based on an indicator,wherein the indicator is carried via one of an additional bit in the ULgrant, a reserved bit in the RAR, an additional bit in the RAR otherthan the UL grant, a new field in a medium access control (MAC) headerfor the RAR, and a reserved state indicated by a field of the UL grant.

Example 18 includes the apparatus of Example 17, wherein the UL grantcomprises a modulation and coding scheme (MCS)/transport block size(TBS) indication field, wherein the MCS/TBS indication field comprisesless bits than that for a random access procedure without EDT.

Example 19 includes the apparatus of Example 17, wherein the UL grantcomprises a MCS/TBS indication field, wherein the MCS/TBS indicationfield comprises more bits than that for a random access procedurewithout EDT.

Example 20 includes the apparatus of Example 17, wherein the UL grantcomprises a MCS/TBS indication field, wherein the MCS/TBS indicationfield is configured to indicate a combination of a modulation schemeand/or a coding scheme with a TBS value.

Example 21 includes the apparatus of Example 17, wherein the UL grantcomprises a physical resource block (PRB) assignment field, wherein thePRB assignment field comprises less bits than that for a random accessprocedure without EDT.

Example 22 includes the apparatus of Example 17, wherein the UL grantcomprises at least one of a UL subcarrier spacing field, a Msg3subcarrier allocation field, a resource assignment field and a MCS/TBSindication field, and wherein at least one of the UL subcarrier spacingfield, the Msg3 subcarrier allocation field, the resource assignmentfield and the MCS/TBS indication field comprises less bits than that fora random access procedure without EDT.

Example 23 includes the apparatus of Example 17, wherein one of theadditional bit in the UL grant, the reserved bit in the RAR, and theadditional bit in the RAR other than the UL grant is configured toindicate whether a field in the UL grant is required to be interpretedin a different way from that for a random access procedure without EDT.

Example 24 includes the apparatus of Example 16, wherein the UL grantcomprises a second additional bit to indicate offset to a TBS value.

Example 25 includes the apparatus of Example 16, wherein the processoris configured to determine, when the UE transmits a physical randomaccess channel (PRACH) sequence via a PRACH resource that is dedicatedfor the EDT or the UE transmits a PRACH sequence dedicated for the EDT,that the UL grant is used for scheduling of EDT.

Example 26 includes the apparatus of Example 16, wherein the UL granthas a size that is different from that for a random access procedurewithout EDT.

Example 27 includes the apparatus of Example 26, wherein the size of theUL grant is indicated by an additional field in a MAC header for theRAR.

Example 28 includes the apparatus of Example 16, wherein the processoris configured to determine that the UL grant is used for scheduling ofEDT, wherein the UL grant has a size that is the same as that of an ULgrant in the RAR in a random access procedure without EDT.

Example 29 includes the apparatus of Example 16, wherein the UL grantcomprises a MCS/TBS indication field, wherein the MCS/TBS indicationfield is interpreted in a different way from that for a random accessprocedure without EDT.

Example 30 includes the apparatus of Example 16, wherein the RAR has aRAR format and size that is the same as that for a random accessprocedure without EDT.

Example 31 includes the apparatus of Example 16, wherein the processoris configured to perform a random access procedure without EDT whendetermining the UL grant is not used for scheduling of EDT.

Example 32 includes an apparatus for a user equipment (UE), comprising:a processor configured to: determine whether to monitor an explicitacknowledge (ACK) in response to Msg3; and monitor the explicit ACK whenit is determined to monitor the explicit ACK; and a radio frequency (RF)interface to: receive the explicit ACK.

Example 33 includes the apparatus of Example 32, wherein whether tomonitor the explicit ACK is determined based on at least one of Msg2,predefinition, and a system information (SI) message.

Example 34 includes the apparatus of Example 32, wherein a new radionetwork temporary identity (RNTI) is defined for physical downlinkcontrol channel (PDCCH) for scheduling Msg2, to indicate the explicitACK.

Example 35 includes the apparatus of Example 32, wherein a temporarycell radio network temporary identity (Temp C-RNTI) is used for PDCCHfor scheduling Msg2, to indicate the explicit ACK.

Example 36 includes the apparatus of Example 32, wherein a first unusedvalue or a first reserved state indicated by a field of Msg2 isconfigured to indicate the explicit ACK.

Example 37 includes the apparatus of Example 32, wherein a second unusedvalue or a second reserved state indicated by a field of Msg2 isconfigured to indicate the UE to go to an idle mode after successfultransmission of Msg3 that comprises early data transmission (EDT).

Example 38 includes the apparatus of Example 32, wherein a third unusedvalue or a third reserved state indicated by a field of Msg2 isconfigured to indicate the UE to go to an idle mode after successfulreception of Msg4 that comprises early data transmission (EDT).

Example 39 includes the apparatus of Example 32, wherein the processoris configured to, after the explicit ACK is received, control the UE togo to an idle mode.

Example 40 includes the apparatus of Example 39, wherein the explicitACK comprises contention resolution related information.

Example 41 includes the apparatus of Example 32, wherein the processoris configured to, after the explicit ACK is received, control the UE tomonitor PDCCH that schedules Msg3 retransmission or Msg4.

Example 42 includes the apparatus of Example 32, wherein the processoris configured to determine, based on Msg2, whether to go to an idle modeor continue to monitor for PDCCH for scheduling of Msg3 retransmissionor Msg4 upon reception of the explicit ACK.

Example 43 includes the apparatus of Example 32, wherein the processoris configured to monitor PDCCH that schedules Msg4 or Msg3retransmission simultaneously with the explicit ACK.

Example 44 includes the apparatus of Example 32, wherein the processoris configured to: monitor the explicit ACK during a monitoring window;and monitor PDCCH that schedules Msg3 retransmission or Msg4 outside themonitoring window.

Example 45 includes an apparatus for a user equipment (UE), comprising:a processor configured to: determine, based on an indicator, whether toallow the UE to go to an idle mode upon expiration of a timer aftertransmission of an acknowledge (ACK) in response to Msg4; and a radiofrequency (RF) interface to: send the ACK to an access node thattransmits the Msg4.

Example 46 includes the apparatus of Example 45, wherein the indicatoris carried in at least one of a system information (SI) message, Msg2,and physical downlink control channel (PDCCH) that schedulestransmission or retransmission of the Msg4.

Example 47 includes the apparatus of Example 45, wherein the timer ispredefined or configured by a SI message.

Example 48 includes the apparatus of Example 45, wherein the timer ispredefined or configured based on CE levels.

Example 49 includes the apparatus of Example 45, wherein a new radionetwork temporary identity (RNTI) is defined for physical downlinkcontrol channel (PDCCH) that schedules transmission or retransmission ofthe Msg4 to indicate the UE to go to the idle mode after successfultransmission of the ACK for the Msg 4.

Example 50 includes the apparatus of Example 45, wherein an unused valueor a reserved state indicated by a field of Msg2 is configured toindicate the UE to go to the idle mode after successful transmission ofthe ACK for the Msg 4.

Example 51 includes an apparatus for a user equipment (UE), comprising:a processor configured to: determine a first candidate transport blocksize (TBS) value as the largest candidate TBS value of a plurality ofcandidate TBS values; and determine, based on the first candidate TBSvalue, a target TBS value for transmission of Msg3 with early datatransmission (EDT) that is transmitted during a random access procedure;and a memory interface to store the first candidate TBS value.

Example 52 includes the apparatus of Example 51, wherein the firstcandidate TBS value is determined based on a maximum TBS value indicatedby a system information (SI) message.

Example 53 includes the apparatus of Example 52, wherein the firstcandidate TBS value is determined to be equal to the maximum TBS value.

Example 54 includes the apparatus of Example 52, wherein the firstcandidate TBS value is determined further based on a number of resourceallocation units allocated to the UE.

Example 55 includes the apparatus of Example 54, wherein the firstcandidate TBS value is determined to be a TBS value of a plurality ofTBS values corresponding to the allocated number of resource allocationunits, wherein the TBS value is the largest one of the plurality of TBSvalues that is equal to or smaller than the maximum TBS value.

Example 56 includes the apparatus of Example 52, wherein the processoris further configured to: determine a second candidate TBS value of theplurality of candidate TBS values based on a modulation and codingscheme (MCS)/TBS indication field in an UL grant for the Msg3 with EDT,wherein the target TBS value for transmission of the Msg3 with EDT isdetermined based on both of the first candidate TBS value and the secondcandidate TBS value.

Example 57 includes the apparatus of Example 56, wherein the processoris further configured to: determine one or more remaining candidate TBSvalues of the plurality of candidate TBS values based on the firstcandidate TBS value and the second candidate TBS value, wherein thetarget TBS value for transmission of the Msg3 with EDT is determinedbased on the first candidate TBS value, the second candidate TBS valueand the one or more remaining candidate TBS values.

Example 58 includes the apparatus of Example 51, wherein the firstcandidate TBS value is determined based on a MCS/TBS indication field inan uplink (UL) grant for the Msg3 with EDT.

Example 59 includes the apparatus of Example 51, wherein the processoris further configured to: determine one or more remaining candidate TBSvalues of the plurality of candidate TBS values based on the firstcandidate TBS value, wherein the one or more remaining candidate TBSvalues are smaller than the first candidate TBS value, and wherein thetarget TBS value for transmission of the Msg3 with EDT is determinedbased on both of the first candidate TBS value and the one or moreremaining candidate TBS values.

Example 60 includes the apparatus of Example 59, wherein the one or moreremaining candidate TBS values are determined based on a mapping betweenthe first candidate TBS value and the one or more remaining candidateTBS values.

Example 61 includes the apparatus of Example 60, wherein the mappingincludes a table indicating the first candidate TBS value andcorresponding one or more remaining candidate TBS values.

Example 62 includes the apparatus of Example 60, wherein the mappingincludes a function between the first candidate TBS value and the one ormore remaining candidate TBS values.

Example 63 includes the apparatus of Example 51, wherein maximum of anumber of the plurality of candidate TBS values is 4.

Example 64 includes the apparatus of Example 51, wherein the processoris further configured to use the same frequency domain resource for allof the plurality of candidate TBS values.

Example 65 includes the apparatus of Example 64, wherein the frequencydomain resource is indicated by an uplink (UL) grant for thetransmission of Msg3 from an access node.

Example 66 includes the apparatus of any of Examples 51 to 65, whereineach of the plurality of candidate TBS values is indicated by arespective TBS index.

Example 67 includes an apparatus for a user equipment (UE), comprising:a radio frequency (RF) interface to: receive a modulation and codingscheme (MCS)/transport block size (TBS) indication field of an uplink(UL) grant or a resource assignment field from an access node; and aprocessor configured to: receive the MCS/TBS indication field or theresource assignment field from the RF interface; and determine, based onthe MCS/TBS indication field or the resource assignment field, a numberof resource allocation units for Msg3 with early data transmission (EDT)that is transmitted during a random access procedure.

Example 68 includes the apparatus of Example 67, wherein the number ofresource allocation units is determined for all of a plurality ofcandidate TBS values available to the UE.

Example 69 includes the apparatus of Example 67, wherein the number ofresource allocation units is determined for a first candidate TBS valueof a plurality of candidate TBS values available to the UE.

Example 70 includes the apparatus of Example 69, wherein the firstcandidate TBS value is the largest one among the plurality of candidateTBS values.

Example 71 includes the apparatus of Example 69, wherein a number ofresource allocation units for a second candidate TBS value of theplurality of candidate TBS values is determined based on a mappingbetween the first candidate TBS value and the second candidate TBSvalue.

Example 72 includes the apparatus of Example 69, wherein the number ofresource allocation units for the first candidate TBS value isdetermined based on a first portion of bits in the MCS/TBS indicationfield.

Example 73 includes the apparatus of Example 72, wherein a number ofresource allocation units for a second candidate TBS value of theplurality of candidate TBS values is determined based on a secondportion of bits in the MCS/TBS indication field.

Example 74 includes the apparatus of Example 73, wherein the secondportion of bits in the MCS/TBS indication field is configured toindicate whether the number of resource allocation units for the secondcandidate TBS value is equal to a predefined number.

Example 75 includes the apparatus of Example 67, wherein the number ofresource allocation units is determined based on a plurality of statesindicated by the MCS/TBS indication field.

Example 76 includes the apparatus of Example 75, wherein the number ofresource allocation units is determined further based on a maximum TBSvalue indicated by the access node.

Example 77 includes the apparatus of Example 75, wherein a number ofresource allocation units for a first candidate TBS value of a pluralityof candidate TBS values available to the UE is determined based on afirst portion of the plurality of states indicated by the MCS/TBSindication field.

Example 78 includes the apparatus of Example 77, wherein a number ofresource allocation units for a second candidate TBS value of theplurality of candidate TBS values is determined based on a secondportion of the plurality of states indicated by the MCS/TBS indicationfield.

Example 79 includes the apparatus of Example 78, wherein the secondportion of the plurality of states indicated by the MCS/TBS indicationfield is configured to indicate whether the number of resourceallocation units for the second candidate TBS value is equal to apredefined number.

Example 80 includes the apparatus of Example 67, wherein the processoris further configured to determine a modulation scheme and/or a codingscheme for the Msg3 based on the MCS/TBS indication field.

Example 81 includes the apparatus of Example 80, wherein the modulationscheme comprises QPSK when the Msg3 is transmitted with a multi-tonemode.

Example 82 includes the apparatus of Example 80, wherein the modulationscheme comprises pi/2 binary phase shift keying (BPSK) and pi/4quadrature phase shift keying (QPSK) when the Msg3 is transmitted with asingle-tone mode.

Example 83 includes the apparatus of Example 82, wherein the pi/4 QPSKis used for the Msg3 transmitted with the single-tone mode irrespectiveof TBS values and the number of resource allocation units.

Example 84 includes the apparatus of Example 82, wherein selection ofthe pi/2 BPSK and the pi/4 QPSK is based on TBS values and the number ofresource allocation units.

Example 85 includes the apparatus of Example 84, wherein the modulationscheme comprises pi/2 BPSK when TBS value is 328 and the number ofresource allocation units is 8 or 10; otherwise the modulation schemecomprises pi/4 QPSK.

Example 86 includes the apparatus of Example 67 to 85, wherein theresource assignment field comprises one of physical resource block (PRB)assignment field and resource unit (RU) assignment field.

Example 87 includes the apparatus of any of Examples 67 to 85, whereinthe resource allocation units comprise one of physical resource blocks(PRBs), resource units (RUs), and subcarriers.

Example 88 includes an apparatus for a user equipment (UE), comprising:a processor configured to: decode a repetition number field of an uplink(UL) grant for Msg3 with early data transmission (EDT) that istransmitted during a random access procedure to obtain a number ofrepetitions indicated by the repetition number field; and determine anumber of repetitions for a first candidate transport block size (TBS)value of a plurality of candidate TBS values based on the number ofrepetitions indicated by the repetition number field; and a memoryinterface to store the number of repetitions for the first candidate TBSvalue.

Example 89 includes the apparatus of Example 88, wherein the processoris further configured to determine a number of repetitions for each ofthe plurality of candidate TBS values to be equal to the number ofrepetitions indicated by the repetition number field.

Example 90 includes the apparatus of Example 88, wherein the processoris further configured to determine the number of repetitions indicatedby the repetition number field as the number of repetitions for thefirst candidate TBS value.

Example 91 includes the apparatus of Example 90, wherein the firstcandidate TBS value is the largest one among the plurality of candidateTBS values.

Example 92 includes the apparatus of Example 91, wherein the processoris further configured to determine a number of repetitions for a secondcandidate TBS value of the plurality of candidate TBS values based on amapping between the number of repetitions for the first candidate TBSvalue and the number of repetitions for the second candidate TBS value.

Example 93 includes the apparatus of Example 92, wherein the number ofrepetitions for the first candidate TBS value is greater than the numberof repetitions for the second candidate TBS value.

Example 94 includes the apparatus of Example 90, wherein the processoris further configured to determine a number of repetitions for a secondcandidate TBS value of the plurality of candidate TBS values based on aportion of bits in a modulation and coding scheme (MCS)/TBS indicationfield of the UL grant or a portion of states indicated by the MCS/TBSindication field.

Example 95 includes the apparatus of Example 94, wherein the portion ofbits in the MCS/TBS indication field or the portion of states indicatedby the MCS/TBS indication field is configured to indicate whether thenumber of repetitions for the second candidate TBS value is equal to apredefined number.

Example 96 includes the apparatus of Example 88, wherein the processoris further configured to determine the number of repetitions for thefirst candidate TBS value and a number of repetitions for a secondcandidate TBS value of the plurality of candidate TBS values based on amaximum TBS value configured by an access node serving the UE.

Example 97 includes the apparatus of Example 96, wherein the number ofrepetitions for the first candidate TBS value and the number ofrepetitions for the second candidate TBS value are determined furtherbased on a mapping between the number of repetitions indicated by therepetition number field and each of the number of repetitions for thefirst candidate TBS value and the number of repetitions for the secondcandidate TBS value.

Example 98 includes the apparatus of Example 97, wherein the mappingcomprises one or more sets of scaling factors for the number ofrepetitions for the first candidate TBS value and the number ofrepetitions for the second candidate TBS value with respect to thenumber of repetitions indicated by the repetition number field.

Example 99 includes the apparatus of Example 98, wherein the one or moresets of scaling factors comprise more than one sets of scaling factors,and wherein which set of scaling factors to be used is indicated byhigher layer signaling or the UL grant.

Example 100 includes the apparatus of Example 98, wherein the one ormore sets of scaling factors comprise one set of scaling factors, andwherein the one set of scaling factors is predefined.

Example 101 includes an apparatus for a user equipment (UE), comprising:a processor configured to: encode an indicator in a Msg3 with early datatransmission (EDT) that is transmitted during a random access procedure,wherein the indicator is configured to indicate a target transport blocksize (TBS) value selected by the UE; and a radio frequency (RF)interface to receive the indicator from the processor.

Example 102 includes the apparatus of Example 101, wherein the indicatorcomprises one or more bits, and wherein a number of the bits is based ona maximum TBS value configured by an access node serving the UE.

Example 103 includes the apparatus of Example 102, wherein the indicatorcomprises one bit when the maximum TBS value is equal to or smaller thana threshold, and the indicator comprises two bits when the maximum TBSvalue is greater than the threshold.

Example 104 includes the apparatus of Example 102, wherein the indicatorcomprises one bit to indicate whether the selected target TBS value isgreater than half of the maximum TBS value.

Example 105 includes the apparatus of Example 101, wherein the indicatorcomprises two bits.

Example 106 includes the apparatus of Example 101, wherein the indicatoris piggybacked following uplink control information (UCI) on physicaluplink share channel (PUSCH).

Example 107 includes the apparatus of Example 101, wherein the indicatoris carried in an initial transmission of the Msg3.

Example 108 includes the apparatus of Example 107, wherein the indicatoris carried in first one or more subframes for the initial transmission.

Example 109 includes the apparatus of Example 101, wherein the indicatoris carried in each of an initial transmission of the Msg3 and one ormore of repetitions of the initial transmission.

Example 110 includes the apparatus of Example 109, wherein a number ofthe one or more repetitions to carry the indicator is determined basedon at least one of predefinition, higher layer signaling, a number ofrepetitions of the initial transmission to be used for the smallest TBSvalue available to the UE, a maximum TBS value configured by an accessnode serving the UE, and a number of repetitions of the initialtransmission indicated by the access node.

Example 111 includes the apparatus of Example 109, wherein the indicatoris carried in first one or more subframes for each of the initialtransmission and the one or more repetitions.

Example 112 includes the apparatus of Example 108 or 111, wherein anumber of the one or more repetitions to carry the indicator isdetermined based on at least one of predefinition, higher layersignaling, a number of repetitions of the initial transmission indicatedby an access node serving the UE, a maximum TBS value configured by theaccess node, and a number of subframes for the maximum TBS value.

Example 113 includes the apparatus of Example 101, wherein the indicatoris carried in first one or more symbols within each of one or moresubframes.

Example 114 includes the apparatus of Example 113, wherein the one ormore subframes comprise a subframe for a repetition of an initialtransmission of the Msg3.

Example 115 includes the apparatus of Example 101, wherein the indicatoris carried in a demodulation reference signal (DMRS).

Example 116 includes the apparatus of any of Examples 101 to 115,wherein the processor is further configured to encode a retransmissionof an initial transmission of the Msg3 using the same amount ofresources as that for the initial transmission, when the amount ofresources for the retransmission indicated by an access node is largerthan the amount of resources used by the UE for the initialtransmission.

Example 117 includes the apparatus of any of Examples 101 to 115,wherein the processor is further configured to encode a retransmissionof an initial transmission of the Msg3 using the amount of resourcesindicated by an access node for the retransmission.

Example 118 includes the apparatus of any of Examples 101 to 117,wherein the UE is operable in a narrowband internet of thing (NB IoT)system or an enhanced machine type communication (eMTC) system.

Example 119 includes a method performed by a user equipment (UE),comprising: encoding a physical random access channel (PRACH) sequencefrom a plurality of PRACH sequence for transmission via a PRACH toperform a random access procedure, wherein indication of support ofearly data transmission (EDT) that is transmitted during the randomaccess procedure is based on at least one of the plurality of PRACHsequences, higher layer signaling, PRACH resources, PRACH formats, and apayload from the UE.

Example 120 includes the method of Example 119, wherein the EDTcomprises uplink (UL) transmission and downlink (DL) transmission.

Example 121 includes the method of Example 119, wherein the higher layersignaling comprises at least one of a system information (SI) messageand dedicated higher layer signaling.

Example 122 includes the method of Example 119, wherein the EDT isenabled based on coverage enhancement (CE) levels.

Example 123 includes the method of Example 119, wherein the PRACHresources are divided into different partitions, and one or morepartitions of the PRACH resources are configured to support the EDT.

Example 124 includes the method of Example 123, wherein the PRACHresources comprise at least one of time resources and frequencyresources.

Example 125 includes the method of Example 124, wherein differentfrequency hopping patterns are configured for different partitions ofthe PRACH resources.

Example 126 includes the method of Example 119, wherein the plurality ofPRACH sequences are divided into different partitions, and one or morepartitions of the plurality of PRACH sequences are configured to supportthe EDT.

Example 127 includes the method of Example 126, wherein the partitionsof the plurality of PRACH sequences are divided based on at least one ofroot indexes and cyclic shifts.

Example 128 includes the method of Example 123 or 126, wherein a numberof the partitions of the PRACH resources or a number of the plurality ofPRACH sequences is configured to indicate support and/or requirement ofmultiple transport block size (TBS) values for the EDT.

Example 129 includes the method of Example 123 or 126, wherein thepartitions of the PRACH resources or the plurality of PRACH sequencesare further divided for different CE levels.

Example 130 includes the method of Example 123 or 126, wherein thepartitions of the PRACH resources or the plurality of PRACH sequencesare further divided for UL transmission and DL transmission of the EDTseparately or for both of the UL transmission and the DL transmission ofthe EDT.

Example 131 includes the method of Example 119, wherein the PRACHformats comprises single-tone PRACH and multi-tone PRACH.

Example 132 includes the method of Example 119, wherein the payload fromthe UE is transmitted following the PRACH sequence to indicate whetherthe UE supports the EDT or not.

Example 133 includes the method of Example 119, wherein the payload isfurther configured to indicate a desired TBS value for UL transmissionof the EDT.

Example 134 includes a method performed by a user equipment (UE),comprising: receiving a random access response (RAR) from an accessnode; decoding the RAR to obtain an uplink (UL) grant; and determiningwhether the UL grant is used for scheduling of early data transmission(EDT) that is transmitted during a random access procedure.

Example 135 includes the method of Example 134, wherein whether the ULgrant is used for scheduling of EDT is determined based on an indicator,wherein the indicator is carried via one of an additional bit in the ULgrant, a reserved bit in the RAR, an additional bit in the RAR otherthan the UL grant, a new field in a medium access control (MAC) headerfor the RAR, and a reserved state indicated by a field of the UL grant.

Example 136 includes the method of Example 135, wherein the UL grantcomprises a modulation and coding scheme (MCS)/transport block size(TBS) indication field, wherein the MCS/TBS indication field comprisesless bits than that for a random access procedure without EDT.

Example 137 includes the method of Example 135, wherein the UL grantcomprises a MCS/TBS indication field, wherein the MCS/TBS indicationfield comprises more bits than that for a random access procedurewithout EDT.

Example 138 includes the method of Example 135, wherein the UL grantcomprises a MCS/TBS indication field, wherein the MCS/TBS indicationfield is configured to indicate a combination of a modulation schemeand/or a coding scheme with a TBS value.

Example 139 includes the method of Example 135, wherein the UL grantcomprises a physical resource block (PRB) assignment field, wherein thePRB assignment field comprises less bits than that for a random accessprocedure without EDT.

Example 140 includes the method of Example 135, wherein the UL grantcomprises at least one of a UL subcarrier spacing field, a Msg3subcarrier allocation field, a resource assignment field and a MCS/TBSindication field, and wherein at least one of the UL subcarrier spacingfield, the Msg3 subcarrier allocation field, the resource assignmentfield and the MCS/TBS indication field comprises less bits than that fora random access procedure without EDT.

Example 141 includes the method of Example 135, wherein one of theadditional bit in the UL grant, the reserved bit in the RAR, and theadditional bit in the RAR other than the UL grant is configured toindicate whether a field in the UL grant is required to be interpretedin a different way from that for a random access procedure without EDT.

Example 142 includes the method of Example 134, wherein the UL grantcomprises a second additional bit to indicate offset to a TBS value.

Example 143 includes the method of Example 134, further comprising:determining, when the UE transmits a physical random access channel(PRACH) sequence via a PRACH resource that is dedicated for the EDT orthe UE transmits a PRACH sequence dedicated for the EDT, that the ULgrant is used for scheduling of EDT.

Example 144 includes the method of Example 134, wherein the UL grant hasa size that is different from that for a random access procedure withoutEDT.

Example 145 includes the method of Example 144, wherein the size of theUL grant is indicated by an additional field in a MAC header for theRAR.

Example 146 includes the method of Example 134, further comprisingdetermining that the UL grant is used for scheduling of EDT, wherein theUL grant has a size that is the same as that of an UL grant in the RARin a random access procedure without EDT.

Example 147 includes the method of Example 134, wherein the UL grantcomprises a MCS/TBS indication field, wherein the MCS/TBS indicationfield is interpreted in a different way from that for a random accessprocedure without EDT.

Example 148 includes the method of Example 134, wherein the RAR has aRAR format and size that is the same as that for a random accessprocedure without EDT.

Example 149 includes the method of Example 134, further comprising:performing a random access procedure without EDT when determining the ULgrant is not used for scheduling of EDT.

Example 150 includes a method performed by a user equipment (UE),comprising: determining whether to monitor an explicit acknowledge (ACK)in response to Msg3; and monitoring the explicit ACK when it isdetermined to monitor the explicit ACK.

Example 151 includes the method of Example 150, wherein whether tomonitor the explicit ACK is determined based on at least one of Msg2,predefinition, and a system information (SI) message.

Example 152 includes the method of Example 150, wherein a new radionetwork temporary identity (RNTI) is defined for physical downlinkcontrol channel (PDCCH) for scheduling Msg2, to indicate the explicitACK.

Example 153 includes the method of Example 150, wherein a temporary cellradio network temporary identity (Temp C-RNTI) is used for PDCCH forscheduling Msg2, to indicate the explicit ACK.

Example 154 includes the method of Example 150, wherein a first unusedvalue or a first reserved state indicated by a field of Msg2 isconfigured to indicate the explicit ACK.

Example 155 includes the method of Example 150, wherein a second unusedvalue or a second reserved state indicated by a field of Msg2 isconfigured to indicate the UE to go to an idle mode after successfultransmission of Msg3 that comprises early data transmission (EDT).

Example 156 includes the method of Example 150, wherein a third unusedvalue or a third reserved state indicated by a field of Msg2 isconfigured to indicate the UE to go to an idle mode after successfulreception of Msg4 that comprises early data transmission (EDT).

Example 157 includes the method of Example 150, further comprising:controlling, after the explicit ACK is received, the UE to go to an idlemode.

Example 158 includes the method of Example 157, wherein the explicit ACKcomprises contention resolution related information.

Example 159 includes the method of Example 150, further comprising:controlling, after the explicit ACK is received, the UE to monitor PDCCHthat schedules Msg3 retransmission or Msg4.

Example 160 includes the method of Example 150, further comprising:determining, based on Msg2, whether to go to an idle mode or continue tomonitor for PDCCH for scheduling of Msg3 retransmission or Msg4 uponreception of the explicit ACK.

Example 161 includes the method of Example 150, further comprising:monitoring PDCCH that schedules Msg3 retransmission or Msg4simultaneously with the explicit ACK.

Example 162 includes the method of Example 150, further comprising:monitoring the explicit ACK during a monitoring window; and monitoringPDCCH that schedules Msg3 retransmission or Msg4 outside the monitoringwindow.

Example 163. A method performed by a user equipment (UE), comprising:determining, based on an indicator, whether to allow the UE to go to anidle mode upon expiration of a timer after transmission of anacknowledge (ACK) in response to Msg4; and sending the ACK to an accessnode that transmits the Msg4.

Example 164 includes the method of Example 163, wherein the indicator iscarried in at least one of a system information (SI) message, Msg2, andphysical downlink control channel (PDCCH) that schedules transmission orretransmission of the Msg4.

Example 165 includes the method of Example 163, wherein the timer ispredefined or configured by a SI message.

Example 166 includes the method of Example 163, wherein the timer ispredefined or configured based on CE levels.

Example 167 includes the method of Example 163, wherein a new radionetwork temporary identity (RNTI) is defined for physical downlinkcontrol channel (PDCCH) that schedules transmission or retransmission ofthe Msg4 to indicate the UE to go to the idle mode after successfultransmission of the ACK for the Msg 4.

Example 168 includes the method of Example 163, wherein an unused valueor a reserved state indicated by a field of Msg2 is configured toindicate the UE to go to the idle mode after successful transmission ofthe ACK for the Msg 4.

Example 169 includes a method performed by a user equipment (UE),comprising: determining a first candidate transport block size (TBS)value as the largest candidate TBS value of a plurality of candidate TBSvalues; and determining, based on the first candidate TBS value, atarget TBS value for transmission of Msg3 with early data transmission(EDT) that is transmitted during a random access procedure.

Example 170 includes the method of Example 169, wherein the firstcandidate TBS value is determined based on a maximum TBS value indicatedby a system information (SI) message.

Example 171 includes the method of Example 170, wherein the firstcandidate TBS value is determined to be equal to the maximum TBS value.

Example 172 includes the method of Example 170, wherein the firstcandidate TBS value is determined further based on a number of resourceallocation units allocated to the UE.

Example 173 includes the method of Example 172, wherein the firstcandidate TBS value is determined to be a TBS value of a plurality ofTBS values corresponding to the allocated number of resource allocationunits, wherein the TBS value is the largest one of the plurality of TBSvalues that is equal to or smaller than the maximum TBS value.

Example 174 includes the method of Example 170, further comprising:determining a second candidate TBS value of the plurality of candidateTBS values based on a modulation and coding scheme (MCS)/TBS indicationfield in an UL grant for the Msg3 with EDT, wherein the target TBS valuefor transmission of the Msg3 with EDT is determined based on both of thefirst candidate TBS value and the second candidate TBS value.

Example 175 includes the method of Example 174, further comprising:determining one or more remaining candidate TBS values of the pluralityof candidate TBS values based on the first candidate TBS value and thesecond candidate TBS value, wherein the target TBS value fortransmission of the Msg3 with EDT is determined based on the firstcandidate TBS value, the second candidate TBS value and the one or moreremaining candidate TBS values.

Example 176 includes the method of Example 169, wherein the firstcandidate TBS value is determined based on a MCS/TBS indication field inan uplink (UL) grant for the Msg3 with EDT.

Example 177 includes the method of Example 169, further comprising:determining one or more remaining candidate TBS values of the pluralityof candidate TBS values based on the first candidate TBS value, whereinthe one or more remaining candidate TBS values are smaller than thefirst candidate TBS value, and wherein the target TBS value fortransmission of the Msg3 with EDT is determined based on both of thefirst candidate TBS value and the one or more remaining candidate TBSvalues.

Example 178 includes the method of Example 177, wherein the one or moreremaining candidate TBS values are determined based on a mapping betweenthe first candidate TBS value and the one or more remaining candidateTBS values.

Example 179 includes the method of Example 178, wherein the mappingincludes a table indicating the first candidate TBS value andcorresponding one or more remaining candidate TBS values.

Example 180 includes the method of Example 178, wherein the mappingincludes a function between the first candidate TBS value and the one ormore remaining candidate TBS values.

Example 181 includes the method of Example 169, wherein maximum of anumber of the plurality of candidate TBS values is 4.

Example 182 includes the method of Example 169, further comprising:using the same frequency domain resource for all of the plurality ofcandidate TBS values.

Example 183 includes the method of Example 182, wherein the frequencydomain resource is indicated by an uplink (UL) grant for thetransmission of Msg3 from an access node.

Example 184 includes the method of any of Examples 169 to 183, whereineach of the plurality of candidate TBS values is indicated by arespective TBS index.

Example 185 includes a method performed a user equipment (UE),comprising: receiving a modulation and coding scheme (MCS)/transportblock size (TBS) indication field of an uplink (UL) grant or a resourceassignment field from an access node; and determining, based on theMCS/TBS indication field or the resource assignment field, a number ofresource allocation units for Msg3 with early data transmission (EDT)that is transmitted during a random access procedure.

Example 186 includes the method of Example 185, wherein the number ofresource allocation units is determined for all of a plurality ofcandidate TBS values available to the UE.

Example 187 includes the method of Example 185, wherein the number ofresource allocation units is determined for a first candidate TBS valueof a plurality of candidate TBS values available to the UE.

Example 188 includes the method of Example 187, wherein the firstcandidate TBS value is the largest one among the plurality of candidateTBS values.

Example 189 includes the method of Example 187, wherein a number ofresource allocation units for a second candidate TBS value of theplurality of candidate TBS values is determined based on a mappingbetween the first candidate TBS value and the second candidate TBSvalue.

Example 190 includes the method of Example 187, wherein the number ofresource allocation units for the first candidate TBS value isdetermined based on a first portion of bits in the MCS/TBS indicationfield.

Example 191 includes the method of Example 190, wherein a number ofresource allocation units for a second candidate TBS value of theplurality of candidate TBS values is determined based on a secondportion of bits in the MCS/TBS indication field.

Example 192 includes the method of Example 191, wherein the secondportion of bits in the MCS/TBS indication field is configured toindicate whether the number of resource allocation units for the secondcandidate TBS value is equal to a predefined number.

Example 193 includes the method of Example 185, wherein the number ofresource allocation units is determined based on a plurality of statesindicated by the MCS/TBS indication field.

Example 194 includes the method of Example 193, wherein the number ofresource allocation units is determined further based on a maximum TBSvalue indicated by the access node.

Example 195 includes the method of Example 193, wherein a number ofresource allocation units for a first candidate TBS value of a pluralityof candidate TBS values available to the UE is determined based on afirst portion of the plurality of states indicated by the MCS/TBSindication field.

Example 196 includes the method of Example 195, wherein a number ofresource allocation units for a second candidate TBS value of theplurality of candidate TBS values is determined based on a secondportion of the plurality of states indicated by the MCS/TBS indicationfield.

Example 197 includes the method of Example 196, wherein the secondportion of the plurality of states indicated by the MCS/TBS indicationfield is configured to indicate whether the number of resourceallocation units for the second candidate TBS value is equal to apredefined number.

Example 198 includes the method of Example 185, further comprising:determining a modulation scheme and/or a coding scheme for the Msg3based on the MCS/TBS indication field.

Example 199 includes the method of Example 198, wherein the modulationscheme comprises QPSK when the Msg3 is transmitted with a multi-tonemode.

Example 200 includes the method of Example 198, wherein the modulationscheme comprises pi/2 binary phase shift keying (BPSK) and pi/4quadrature phase shift keying (QPSK) when the Msg3 is transmitted with asingle-tone mode.

Example 201 includes the method of Example 200, wherein the pi/4 QPSK isused for the Msg3 transmitted with the single-tone mode irrespective ofTBS values and the number of resource allocation units.

Example 202 includes the method of Example 200, wherein selection of thepi/2 BPSK and the pi/4 QPSK is based on TBS values and the number ofresource allocation units.

Example 203 includes the method of Example 202, wherein the modulationscheme comprises pi/2 BPSK when TBS value is 328 and the number ofresource allocation units is 8 or 10; otherwise the modulation schemecomprises pi/4 QPSK.

Example 204 includes the method of Example 185 to 203, wherein theresource assignment field comprises one of physical resource block (PRB)assignment field and resource unit (RU) assignment field.

Example 205 includes the method of any of Examples 185 to 204, whereinthe resource allocation units comprise one of physical resource blocks(PRBs), resource units (RUs), and subcarriers.

Example 206 includes a method performed by a user equipment (UE),comprising: decoding a repetition number field of an uplink (UL) grantfor Msg3 with early data transmission (EDT) that is transmitted during arandom access procedure to obtain a number of repetitions indicated bythe repetition number field; and determining a number of repetitions fora first candidate transport block size (TBS) value of a plurality ofcandidate TBS values based on the number of repetitions indicated by therepetition number field.

Example 207 includes the method of Example 206, further comprising:determining a number of repetitions for each of the plurality ofcandidate TBS values to be equal to the number of repetitions indicatedby the repetition number field.

Example 208 includes the method of Example 206, further comprising:determining the number of repetitions indicated by the repetition numberfield as the number of repetitions for the first candidate TBS value.

Example 209 includes the method of Example 208, wherein the firstcandidate TBS value is the largest one among the plurality of candidateTBS values.

Example 210 includes the method of Example 209, further comprising:determining a number of repetitions for a second candidate TBS value ofthe plurality of candidate TBS values based on a mapping between thenumber of repetitions for the first candidate TBS value and the numberof repetitions for the second candidate TBS value.

Example 211 includes the method of Example 210, wherein the number ofrepetitions for the first candidate TBS value is greater than the numberof repetitions for the second candidate TBS value.

Example 212 includes the method of Example 208, further comprising:determining a number of repetitions for a second candidate TBS value ofthe plurality of candidate TBS values based on a portion of bits in amodulation and coding scheme (MCS)/TBS indication field of the UL grantor a portion of states indicated by the MCS/TBS indication field.

Example 213 includes the method of Example 212, wherein the portion ofbits in the MCS/TBS indication field or the portion of states indicatedby the MCS/TBS indication field is configured to indicate whether thenumber of repetitions for the second candidate TBS value is equal to apredefined number.

Example 214 includes the method of Example 206, further comprising:determining the number of repetitions for the first candidate TBS valueand a number of repetitions for a second candidate TBS value of theplurality of candidate TBS values based on a maximum TBS valueconfigured by an access node serving the UE.

Example 215 includes the method of Example 214, wherein the number ofrepetitions for the first candidate TBS value and the number ofrepetitions for the second candidate TBS value are determined furtherbased on a mapping between the number of repetitions indicated by therepetition number field and each of the number of repetitions for thefirst candidate TBS value and the number of repetitions for the secondcandidate TBS value.

Example 216 includes the method of Example 215, wherein the mappingcomprises one or more sets of scaling factors for the number ofrepetitions for the first candidate TBS value and the number ofrepetitions for the second candidate TBS value with respect to thenumber of repetitions indicated by the repetition number field.

Example 217 includes the method of Example 216, wherein the one or moresets of scaling factors comprise more than one sets of scaling factors,and wherein which set of scaling factors to be used is indicated byhigher layer signaling or the UL grant.

Example 218 includes the method of Example 216, wherein the one or moresets of scaling factors comprise one set of scaling factors, and whereinthe one set of scaling factors is predefined.

Example 219 includes a method performed by a user equipment (UE),comprising: encoding an indicator in a Msg3 with early data transmission(EDT) that is transmitted during a random access procedure, wherein theindicator is configured to indicate a target transport block size (TBS)value selected by the UE.

Example 220 includes the method of Example 219, wherein the indicatorcomprises one or more bits, and wherein a number of the bits is based ona maximum TBS value configured by an access node serving the UE.

Example 221 includes the method of Example 220, wherein the indicatorcomprises one bit when the maximum TBS value is equal to or smaller thana threshold, and the indicator comprises two bits when the maximum TBSvalue is greater than the threshold.

Example 222 includes the method of Example 220, wherein the indicatorcomprises one bit to indicate whether the selected target TBS value isgreater than half of the maximum TBS value.

Example 223 includes the method of Example 219, wherein the indicatorcomprises two bits.

Example 224 includes the method of Example 219, wherein the indicator ispiggybacked following uplink control information (UCI) on physicaluplink share channel (PUSCH).

Example 225 includes the method of Example 219, wherein the indicator iscarried in an initial transmission of the Msg3.

Example 226 includes the method of Example 225, wherein the indicator iscarried in first one or more subframes for the initial transmission.

Example 227 includes the method of Example 219, wherein the indicator iscarried in each of an initial transmission of the Msg3 and one or moreof repetitions of the initial transmission.

Example 228 includes the method of Example 227, wherein a number of theone or more repetitions to carry the indicator is determined based on atleast one of predefinition, higher layer signaling, a number ofrepetitions of the initial transmission to be used for the smallest TBSvalue available to the UE, a maximum TBS value configured by an accessnode serving the UE, and a number of repetitions of the initialtransmission indicated by the access node.

Example 229 includes the method of Example 227, wherein the indicator iscarried in first one or more subframes for each of the initialtransmission and the one or more repetitions.

Example 230 includes the method of Example 226 or 229, wherein a numberof the one or more repetitions to carry the indicator is determinedbased on at least one of predefinition, higher layer signaling, a numberof repetitions of the initial transmission indicated by an access nodeserving the UE, a maximum TBS value configured by the access node, and anumber of subframes for the maximum TBS value.

Example 231 includes the method of Example 219, wherein the indicator iscarried in first one or more symbols within each of one or moresubframes.

Example 232 includes the method of Example 231, wherein the one or moresubframes comprise a subframe for a repetition of an initialtransmission of the Msg3.

Example 233 includes the method of Example 219, wherein the indicator iscarried in a demodulation reference signal (DMRS).

Example 234 includes the method of any of Examples 219 to 233, furthercomprising: encoding a retransmission of an initial transmission of theMsg3 using the same amount of resources as that for the initialtransmission, when the amount of resources for the retransmissionindicated by an access node is larger than the amount of resources usedby the UE for the initial transmission.

Example 235 includes the method of any of Examples 219 to 233, furthercomprising: encoding a retransmission of an initial transmission of theMsg3 using the amount of resources indicated by an access node for theretransmission.

Example 236 includes the method of any of Examples 219 to 235, whereinthe UE is operable in a narrowband internet of thing (NB IoT) system oran enhanced machine type communication (eMTC) system.

Example 237 includes a non-transitory computer-readable medium havinginstructions stored thereon, the instructions when executed by one ormore processor(s) causing the processor(s) to perform the method of anyof Examples 119-236.

Example 238 includes an apparatus for user equipment (UE), comprisingmeans for performing the actions of the method of any of Examples119-236.

Example 239 includes a user equipment (UE) as shown and described in thedescription.

Example 240 includes an access node (AN) as shown and described in thedescription.

Example 241 includes a method performed at user equipment (UE) as shownand described in the description.

Although certain embodiments have been illustrated and described hereinfor purposes of description, a wide variety of alternate and/orequivalent embodiments or implementations calculated to achieve the samepurposes may be substituted for the embodiments shown and describedwithout departing from the scope of the present disclosure. Thisapplication is intended to cover any adaptations or variations of theembodiments discussed herein. Therefore, it is manifestly intended thatembodiments described herein be limited only by the appended Examplesand the equivalents thereof.

What is claimed is:
 1. An apparatus for a user equipment (UE),comprising: a processor configured to: encode a physical random accesschannel (PRACH) sequence for transmission via a PRACH to perform arandom access procedure, wherein indication of support of early datatransmission (EDT) that is transmitted during the random accessprocedure is based on at least one of higher layer signaling, PRACHresources, PRACH sequences, PRACH formats, or a payload from the UE; andsend the PRACH sequence to a radio frequency (RF) interface; and the RFinterface to receive the PRACH sequence from the processor, wherein thePRACH sequences are divided into different partitions, and one or morepartitions of the PRACH sequences are configured to support the EDT. 2.The apparatus of claim 1, wherein the EDT comprises uplink (UL)transmission and downlink (DL) transmission.
 3. The apparatus of claim1, wherein the higher layer signaling comprises at least one of a systeminformation (SI) message and dedicated higher layer signaling.
 4. Theapparatus of claim 1, wherein the EDT is enabled based on coverageenhancement (CE) levels.
 5. The apparatus of claim 1, wherein the PRACHresources are divided into different partitions, and one or morepartitions of the PRACH resources are configured to support the EDT. 6.The apparatus of claim 5, wherein the PRACH resources comprise one orboth of time resources and frequency resources.
 7. The apparatus ofclaim 6, wherein different frequency hopping patterns are configured fordifferent partitions of the PRACH resources.
 8. The apparatus of claim1, wherein the partitions of the PRACH sequences are divided based onone or both of root indexes and cyclic shifts.
 9. The apparatus of claim1, wherein the number of the partitions of the PRACH resources or PRACHsequences is configured to indicate support and/or requirement ofmultiple transport block size (TBS) values for the EDT.
 10. Theapparatus of claim 1, wherein the partitions of the PRACH resources orPRACH sequences are further divided for different coverage enhancement(CE) levels.
 11. The apparatus of claim 1, wherein the partitions of thePRACH resources or PRACH sequences are further divided for uplink (UL)transmission and downlink (DL) transmission of the EDT separately or forboth of the UL transmission and the DL transmission of the EDT.
 12. Theapparatus of claim 1, wherein the PRACH formats comprises single-tonePRACH and multi-tone PRACH.
 13. The apparatus of claim 1, wherein thepayload from the UE is transmitted following the PRACH sequence toindicate whether the UE supports the EDT or not.
 14. The apparatus ofclaim 1, wherein the payload is further configured to indicate a desiredTBS value for UL transmission of the EDT.
 15. An apparatus for a userequipment (UE), comprising: a radio frequency (RF) interface to receivea random access response (RAR) from an access node; and a processorconfigured to: receive the RAR from the RF interface; decode the RAR toobtain an uplink (UL) grant; and determine whether the UL grant is usedfor scheduling of early data transmission (EDT) that is transmittedduring a random access procedure, wherein whether the UL grant is usedfor scheduling of EDT is determined based on an indicator, wherein theindicator is carried via one of an additional bit in the UL grant, areserved bit in the RAR, an additional bit in the RAR other than the ULgrant, a new field in a medium access control (MAC) header for the RAR,or a reserved state indicated by a field of the UL grant.
 16. Theapparatus of claim 15, wherein the UL grant comprises a modulation andcoding scheme (MCS)/transport block size (TBS) indication field, whereinthe MCS/TBS indication field comprises less bits than that for a randomaccess procedure without EDT.
 17. The apparatus of claim 15, wherein theUL grant comprises a MCS/TBS indication field, wherein the MCS/TBSindication field comprises more bits than that for a random accessprocedure without EDT.
 18. The apparatus of claim 15, wherein the ULgrant comprises a modulation and coding scheme (MCS)/transport blocksize (TBS) indication field, wherein the MCS/TBS indication field isconfigured to indicate a combination of a modulation scheme and a TBSvalue.
 19. The apparatus of claim 15, wherein the UL grant comprises aphysical resource block (PRB) assignment field, wherein the PRBassignment field comprises less bits than that for a random accessprocedure without EDT.
 20. The apparatus of claim 15, wherein the ULgrant comprises at least one of a UL subcarrier spacing field, a Msg3subcarrier allocation field, a resource assignment field and amodulation and coding scheme (MCS)/transport block size (TBS) indicationfield, and wherein at least one of the UL subcarrier spacing field, theMsg3 subcarrier allocation field, the resource assignment field and theMCS/TBS indication field comprises less bits than that for a randomaccess procedure without EDT.
 21. The apparatus of claim 15, wherein oneof the additional bit in the UL grant, the reserved bit in the RAR, andthe additional bit in the RAR other than the UL grant is configured toindicate whether a field in the UL grant is required to be interpretedin a different way from that for a random access procedure without EDT.22. The apparatus of claim 15, wherein the UL grant comprises a secondadditional bit to indicate offset to a transport block size (TBS) value.23. The apparatus of claim 15, wherein the processor is configured todetermine the UL grant is used for scheduling of EDT, when the UEtransmits a physical random access channel (PRACH) sequence via a PRACHresource that is dedicated for the EDT or the UE transmits a PRACHsequence dedicated for the EDT.
 24. An apparatus for a user equipment(UE), comprising: a processor configured to: encode a physical randomaccess channel (PRACH) sequence for transmission via a PRACH to performa random access procedure, wherein indication of support of early datatransmission (EDT) is transmitted during PRACH sequences, wherein thePRACH sequences are divided into different partitions, and one or morepartitions of the PRACH sequences are configured to support the EDT; andsend the PRACH sequence to a radio frequency (RF) interface; and the RFinterface configured to receive the PRACH sequence from the processor.25. The apparatus of claim 24, wherein the partitions of the PRACHsequences are further divided for uplink (UL) transmission and downlink(DL) transmission of the EDT separately, or for both of the ULtransmission and the DL transmission of the EDT.